View source for Headache

{{short description|Pain in the head, neck, or face}}
{{Other uses}}
{{cs1 config|name-list-style=vanc|display-authors=6}}
{{Infobox medical condition (new)
| name          = Headache
| synonym       = Cephalalgia
| image         = Symptoms-headache.jpg
| image_size    = 
| alt           = 
| caption       = Person with a headache
| pronounce     = 
| specialty     = [[Neurology]]
| symptoms      = 
| complications = 
| onset         = 
| duration      = 
| types         = [[Tension headache]], [[cluster headache]], [[sinusitis]], [[migraine]] headache, [[hangover]] headache, [[cold-stimulus headache]] (brain freeze)
| causes        = 
| risks         = 
| diagnosis     = 
| differential  = 
| prevention    = 
| treatment     = [[Over-the-counter drug|Over-the-counter]] [[painkillers]], [[sleep]], drinking water, eating food, head or neck massage
| medication    = 
| prognosis     = 
| frequency     = 
| deaths        = 
}}

<!-- Definition and symptoms -->
A '''headache''', also known as '''cephalalgia''', is the symptom of [[pain]] in the [[face]], [[head]], or [[neck]]. It can occur as a [[migraine]], [[tension-type headache]], or [[cluster headache]].<ref>{{Cite web|title=Headache disorders | date = 8 April 2016 |url=https://www.who.int/news-room/fact-sheets/detail/headache-disorders|access-date=2021-12-14| publisher = The World Health Organization |language=en}}</ref><ref>{{Citation |last=Silberstein |first=Stephen D. |title=Headache |date=2022-03-09 |url=https://onlinelibrary.wiley.com/doi/10.1002/9781119701170.ch32 |work=Clinical Pain Management |pages=336–342 |editor-last=Lynch |editor-first=Mary E. |edition=1 |publisher=Wiley |language=en |doi=10.1002/9781119701170.ch32 |isbn=978-1-119-70115-6 |access-date=2022-04-29 |editor2-last=Craig |editor2-first=Kenneth D. |editor3-last=Peng |editor3-first=Philip W.|url-access=subscription }}</ref> There is an increased risk of [[Depression (mood)|depression]] in those with severe headaches.<ref name=WHO2012/>

<!-- Cause and diagnosis -->
Headaches can occur as a result of many conditions. There are a number of different classification systems for headaches. The most well-recognized is that of the [[International Headache Society]], which classifies it into more than 150 types of [[Primary headache disorder|primary]] and secondary headaches. Causes of headaches may include [[dehydration]]; [[fatigue]]; sleep deprivation; [[Stress (biology)|stress]];<ref>{{Citation |last=Britton |first=Carolyn B. |title=Stress and headache |date=2013 |url=https://www.cambridge.org/core/books/neuropsychiatry-of-headache/stress-and-headache/5589A5C987524A008DCB3EAB29AB6FB2 |work=The Neuropsychiatry of Headache |pages=54–62 |editor-last=Green |editor-first=Mark W. |place=Cambridge |publisher=Cambridge University Press |doi=10.1017/cbo9781139206952.007 |isbn=978-1-107-02620-9 |access-date=2022-04-29 |editor2-last=Muskin |editor2-first=Philip R.|url-access=subscription }}</ref> the effects of medications (overuse) and recreational drugs, including withdrawal; viral infections; loud noises; head injury; rapid ingestion of a very cold food or beverage; and dental or sinus issues (such as [[sinusitis]]).<ref>{{Cite web|url=https://www.mayoclinic.org/symptoms/headache/basics/definition/sym-20050800|title=Headache Causes|website=Mayo Clinic|language=en|access-date=21 October 2019}}</ref>

<!-- Prevention and Treatment -->
Treatment of a headache depends on the underlying cause, but commonly involves [[Analgesic|analgesic (pain medication)]], especially in case of migraine or cluster headaches.<ref>{{Cite web|title=Headache|url=https://www.hopkinsmedicine.org/health/conditions-and-diseases/headache|access-date=2021-12-14 | work = Johns Hopkins Medicine | publisher = The Johns Hopkins University |language=en}}</ref> A headache is one of the most commonly experienced of all physical discomforts.<ref name="Ahmed 124–132">{{cite journal | vauthors = Ahmed F | title = Headache disorders: differentiating and managing the common subtypes | journal = British Journal of Pain | volume = 6 | issue = 3 | pages = 124–132 | date = August 2012 | pmid = 26516483 | pmc = 4590146 | doi = 10.1177/2049463712459691 }}</ref>

<!-- Epidemiology -->
About half of adults have a headache in a given year.<ref name=WHO2012>{{cite web|title=Headache disorders Fact sheet N° 277 | publisher = The World Health Organization | date = 8 April 2016 |url=https://www.who.int/mediacentre/factsheets/fs277/en/|access-date=15 February 2016 |url-status=live|archive-url= https://web.archive.org/web/20160216184228/http://www.who.int/mediacentre/factsheets/fs277/en/ |archive-date=16 February 2016}}</ref> Tension headaches are the most common,<ref name="Ahmed 124–132"/> affecting about 1.6&nbsp;billion people (21.8% of the population) followed by migraine headaches which affect about 848 million (11.7%).<ref>{{cite journal | vauthors = Vos T, Barber RM, Bell B, Bertozzi-Villa A, Biryukov S, Bolliger I, etal | collaboration = Global Burden of Disease Study 2013 Collaborators | title = Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013 | journal = Lancet | volume = 386 | issue = 9995 | pages = 743–800 | date = August 2015 | pmid = 26063472 | pmc = 4561509 | doi = 10.1016/s0140-6736(15)60692-4 }}</ref>
{{TOC limit|3}}

== Causes ==
There are more than 200 types of headaches. Some are harmless and some are [[life-threatening]]. The description of the headache and findings on [[neurological examination]], determine whether additional tests are needed and what treatment is best.<ref name=SIGN>{{cite book |author= Scottish Intercollegiate Network |title= Diagnosis and management of headache in adults |location= Edinburgh |date= November 2008 |isbn= 978-1-905813-39-1 |url= http://www.sign.ac.uk/guidelines/fulltext/107/ |publisher= [[NHS Scotland|NHS Quality Improvement Scotland]] |archive-url= https://web.archive.org/web/20110419031343/http://www.sign.ac.uk/guidelines/fulltext/107/ |archive-date= 19 April 2011 |access-date= 14 July 2010 }}</ref>

Headaches are broadly classified as "primary" or "secondary".<ref>{{cite web|url=http://www.hopkinsmedicine.org/neurology_neurosurgery/specialty_areas/headache/conditions/primary_vs_secondary_headaches.html|title=The Johns Hopkins Headache Center - Primary Exertion Headache| vauthors = Young CB |date=3 January 2012|work=hopkinsmedicine.org|archive-url= https://web.archive.org/web/20140503222313/http://www.hopkinsmedicine.org/neurology_neurosurgery/specialty_areas/headache/conditions/primary_vs_secondary_headaches.html|archive-date=3 May 2014}}</ref> Primary headaches are benign, recurrent headaches not caused by underlying disease or structural problems. For example, [[migraine]] is a type of primary headache. While primary headaches may cause significant daily pain and disability, they are not dangerous from a physiological point of view. Secondary headaches are caused by an underlying disease, like an [[Systemic infection|infection]], [[head injury]], [[vascular disorders]], [[Subarachnoid hemorrhage|brain bleed]], stomach irritation, or [[brain tumor]]. Secondary headaches can be dangerous. Certain "red flags" or warning signs indicate a secondary headache may be dangerous.<ref name="Goadsby">{{cite book | vauthors = Goadsby PJ, Raskin NH | chapter = Chapter 14. Headache | veditors = Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson J, Loscalzo J | title = Harrison's Principles of Internal Medicine | edition = 18th | location = New York, NY | publisher = McGraw-Hill | date = 2012 | isbn = 978-0-07-174890-2 }}</ref>

===Primary===
Ninety percent of all headaches are primary headaches.<ref>{{Cite journal| vauthors = Damayanti Y, Marhaendraputro EA, Santoso WM, Rahmawati D |date=2021-03-02|title= Profile of Primary Patients in Neurological Polyclinic |url= https://jphv.ub.ac.id/index.php/jphv/article/view/19 |journal=Journal of Pain, Headache and Vertigo |volume=2|issue=1|pages=1–4|doi=10.21776/ub.jphv.2021.002.01.1|s2cid=233777394|issn=2723-3960|doi-access=free}}</ref> Primary headaches usually first start when people are between 20 and 40 years old.<ref>{{cite journal | vauthors = Straube A, Andreou A | title = Primary headaches during lifespan | journal = The Journal of Headache and Pain | volume = 20 | issue = 1 | article-number = 35 | date = April 2019 | pmid = 30961531 | pmc = 6734460 | doi = 10.1186/s10194-019-0985-0 | doi-access = free }}</ref><ref name="Clinch">{{cite book|title=Clinch C. Chapter 28. Evaluation & Management of Headache - CURRENT Diagnosis & Treatment in Family Medicine | edition = Third | series = Lange Current Series | vauthors = South-Paul JE, Matheny SC, Lewis EL |isbn=978-0-07-162436-7 |publisher=McGraw-Hill|year=2011}}</ref> The most common types of primary headaches are migraines and tension-type headaches.<ref name="Clinch" /> They have different characteristics. Migraines typically present with pulsing head pain, nausea, photophobia (sensitivity to light) and phonophobia (sensitivity to sound).<ref>{{Cite web|title=Migraine - Symptoms and causes|url=https://www.mayoclinic.org/diseases-conditions/migraine-headache/symptoms-causes/syc-20360201|access-date=2021-12-15|website=Mayo Clinic|language=en}}</ref> Tension-type headaches usually present with non-pulsing "bandlike" pressure on both sides of the head, not accompanied by other symptoms.<ref>{{Cite web|title=Tension Headaches|url=https://www.hopkinsmedicine.org/health/conditions-and-diseases/headache/tension-headaches|access-date=2021-12-15|website=www.hopkinsmedicine.org|date=8 August 2021 |language=en}}</ref><ref name="Detsky">{{cite journal | vauthors = Detsky ME, McDonald DR, Baerlocher MO, Tomlinson GA, McCrory DC, Booth CM | title = Does this patient with headache have a migraine or need neuroimaging? | journal = JAMA | volume = 296 | issue = 10 | pages = 1274–1283 | date = September 2006 | pmid = 16968852 | doi = 10.1001/jama.296.10.1274 }}</ref> Such kind of headaches may be further classified into-[[Tension headache|episodic]] and chronic tension type headaches<ref>{{Cite web|title=Tension headache - Symptoms and causes|url=https://www.mayoclinic.org/diseases-conditions/tension-headache/symptoms-causes/syc-20353977|access-date=2021-12-15|website=Mayo Clinic|language=en}}</ref> Other very rare types of primary headaches include:<ref name="Goadsby" />
* [[cluster headache]]s: short episodes (15–180 minutes) of severe pain, usually around one eye, with autonomic symptoms (tearing, red eye, nasal congestion) which occur at the same time every day. Cluster headaches can be treated with triptans and prevented with prednisone, ergotamine or lithium.
* [[trigeminal neuralgia]] or [[occipital neuralgia]]: shooting face pain
* [[hemicrania continua]]: continuous unilateral pain with episodes of severe pain. Hemicrania continua can be relieved by the medication [[Indometacin|indomethacin]].
* [[Ophthalmodynia periodica|primary stabbing headache]]: recurrent episodes of stabbing "ice pick pain" or "jabs and jolts" for 1 second to several minutes without autonomic symptoms (tearing, red eye, nasal congestion). These headaches can be treated with indomethacin.
* primary cough headache: starts suddenly and lasts for several minutes after coughing, sneezing or straining (anything that may increase pressure in the head). Serious causes (see secondary headaches red flag section) must be ruled out before a diagnosis of "benign" primary cough headache can be made.
* primary exertional headache: throbbing, pulsatile pain which starts during or after exercising, lasting for 5 minutes to 24 hours. The mechanism behind these headaches is unclear, possibly due to straining causing veins in the head to dilate, causing pain. These headaches can be prevented by not exercising too strenuously and can be treated with medications such as indomethacin.
* [[Sexual headache|primary sex headache]]: dull, bilateral headache that starts during sexual activity and becomes much worse during orgasm. These headaches are thought to be due to lower pressure in the head during sex. It is important to realize that headaches that begin during orgasm may be due to a subarachnoid hemorrhage, so serious causes must be ruled out first. These headaches are treated by advising the person to stop sex if they develop a headache. Medications such as [[propranolol]] and [[diltiazem]] can also be helpful.
* [[hypnic headache]]: a moderate-severe headache that starts a few hours after falling asleep and lasts 15–30 minutes. The headache may recur several times during the night. Hypnic headaches are usually in older women. They may be treated with [[lithium (medication)|lithium]].

=== Secondary ===
{{More citations needed section|date=February 2021}}
Headaches may be caused by problems elsewhere in the head or neck. Some of these are not harmful, such as [[cervicogenic headache]] (pain arising from the neck muscles). The excessive use of painkillers can paradoxically cause worsening [[painkiller headache]]s.<ref name=SIGN /><ref name="NHS">{{cite web |title=Headaches |url=https://www.nhs.uk/conditions/headaches/ |website=nhs.uk |language=en |date=8 January 2018}}</ref>

More serious causes of secondary headaches include the following:<ref name="Goadsby" />
* [[meningitis]]: [[inflammation]] of the meninges which presents with fever and meningismus, or stiff neck
* [[Stroke|ischemic stroke]] or a previous stage of the same
* [[Stroke|hemorragic stroke]] or a previous stage of the same
* [[intracranial hemorrhage]] (bleeding inside the brain) because of any origin
* [[subarachnoid hemorrhage]] (with acute, severe headache, stiff neck without fever) because of any origin
* [[intraparenchymal hemorrhage]] (with headache only) because of any origin
* [[ruptured aneurysm]] or [[aneurysm]]
* [[brain tumor]] (a form of cancer): dull headache, worse with exertion and change in position, accompanied by nausea and vomiting. Often, the person will have nausea and vomiting for weeks before the headache starts.
* [[temporal arteritis]]: inflammatory disease of arteries common in the elderly (average age 70) with fever, headache, weight loss, jaw claudication, tender vessels by the temples, polymyalgia rheumatica
* [[Glaucoma|acute closed-angle glaucoma]] (increased pressure in the eyeball): a headache that starts with eye pain, blurry vision, associated with nausea and vomiting. On physical exam, the person will have red eyes and a fixed, mid-dilated pupil.
* [[arteriovenous malformation]]
* post-ictal headaches: Headaches that happen after a convulsion or other type of seizure, as part of the period after the seizure (the [[post-ictal]] state)
* [[traumatic brain injury]]

[[Gastrointestinal disease|Gastrointestinal disorders]] may cause headaches, including [[Helicobacter pylori]] infection, [[celiac disease]], [[non-celiac gluten sensitivity]], [[irritable bowel syndrome]], [[inflammatory bowel disease]], [[gastroparesis]], and [[List of hepato-biliary diseases|hepatobiliary disorders]].<ref name=LionettiFrancavilla2010>{{cite journal | vauthors = Lionetti E, Francavilla R, Pavone P, Pavone L, Francavilla T, Pulvirenti A, Giugno R, Ruggieri M | title = The neurology of coeliac disease in childhood: what is the evidence? A systematic review and meta-analysis | journal = Developmental Medicine and Child Neurology | volume = 52 | issue = 8 | pages = 700–707 | date = August 2010 | pmid = 20345955 | doi = 10.1111/j.1469-8749.2010.03647.x | type = Systematic review and meta-analysis | s2cid = 205611320 | doi-access = free }}{{open access}}</ref><ref name=AzizHadjivassiliou2015>{{cite journal | vauthors = Aziz I, Hadjivassiliou M, Sanders DS | title = The spectrum of noncoeliac gluten sensitivity | journal = Nature Reviews. Gastroenterology & Hepatology | volume = 12 | issue = 9 | pages = 516–526 | date = September 2015 | pmid = 26122473 | doi = 10.1038/nrgastro.2015.107 | type = Review | s2cid = 2867448 }}</ref><ref name=CamaraLemarroyRodriguezGutierrez2016>{{cite journal | vauthors = Cámara-Lemarroy CR, Rodriguez-Gutierrez R, Monreal-Robles R, Marfil-Rivera A | title = Gastrointestinal disorders associated with migraine: A comprehensive review | journal = World Journal of Gastroenterology | volume = 22 | issue = 36 | pages = 8149–8160 | date = September 2016 | pmid = 27688656 | pmc = 5037083 | doi = 10.3748/wjg.v22.i36.8149 | type = Review | doi-access = free }}</ref> The treatment of the gastrointestinal disorders may lead to a remission or improvement of headaches.<ref name=CamaraLemarroyRodriguezGutierrez2016 />

Migraine headaches are also associated with [[Cyclic Vomiting Syndrome]] (CVS). CVS is characterized by episodes of severe vomiting, and often occur alongside symptoms similar to those of migraine headaches (photophobia, abdominal pain, etc.).<ref>{{cite journal | vauthors = Hasler WL, Levinthal DJ, Tarbell SE, Adams KA, Li BU, Issenman RM, Sarosiek I, Jaradeh SS, Sharaf RN, Sultan S, Venkatesan T | title = Cyclic vomiting syndrome: Pathophysiology, comorbidities, and future research directions | journal = Neurogastroenterology and Motility | volume = 31 | issue = Suppl 2 | article-number = e13607 | date = June 2019 | pmid = 31241816 | pmc = 6899706 | doi = 10.1111/nmo.13607 }}</ref>

== Pathophysiology ==
The [[Human brain|brain]] itself is not sensitive to [[pain]], because it lacks [[nociceptor|pain receptor]]s. However, several areas of the [[head]] and [[neck]] do have pain receptors and can thus sense pain. These include the extracranial arteries, [[middle meningeal artery]], large veins, [[venous sinuses]], cranial and spinal nerves, head and neck muscles, the [[meninges]], [[falx cerebri]], parts of the brainstem, eyes, ears, teeth, and lining of the mouth.<ref name=ACEP2008>{{cite journal | vauthors = Edlow JA, Panagos PD, Godwin SA, Thomas TL, Decker WW | title = Clinical policy: critical issues in the evaluation and management of adult patients presenting to the emergency department with acute headache | journal = Annals of Emergency Medicine | volume = 52 | issue = 4 | pages = 407–436 | date = October 2008 | pmid = 18809105 | doi = 10.1016/j.annemergmed.2008.07.001 | s2cid = 507361 }}</ref><ref name="Clinical Neurology">{{cite book|vauthors = Greenberg D, Aminoff M, Simon R|title=Clinical Neurology 8/E:Chapter 6. Headache & Facial Pain|date=6 May 2012|publisher=McGraw Hill Professional|isbn=978-0-07-175905-2}}</ref> Pial arteries, rather than pial veins are responsible for pain production.<ref name="Goadsby" />

Headaches often result from traction or irritation of the meninges and blood vessels.<ref>{{Cite web |title=headache {{!}} Britannica |url=https://www.britannica.com/science/headache |access-date=2022-04-29 |website=www.britannica.com |language=en}}</ref> The pain receptors may be stimulated by head trauma or tumours and cause headaches. Blood vessel spasms, dilated [[blood vessels]], inflammation or infection of meninges and muscular tension can also stimulate pain receptors.<ref name="Clinical Neurology" /> Once stimulated, a [[nociceptor]] sends a message up the length of the nerve fibre to the nerve cells in the brain, signalling that a part of the body hurts.<ref>{{cite journal | vauthors = Dubin AE, Patapoutian A | title = Nociceptors: the sensors of the pain pathway | journal = The Journal of Clinical Investigation | volume = 120 | issue = 11 | pages = 3760–3772 | date = November 2010 | pmid = 21041958 | pmc = 2964977 | doi = 10.1172/JCI42843 }}</ref>

Primary headaches are more difficult to understand than secondary headaches. The exact mechanisms which cause migraines, tension headaches and cluster headaches are not known.<ref name="Leroux"/> There have been [[Migraine#Cause|different hypotheses]] over time that attempt to explain what happens in the brain to cause these headaches.<ref>{{Cite web|title=How a Migraine Happens|url=https://www.hopkinsmedicine.org/health/conditions-and-diseases/headache/how-a-migraine-happens|access-date=2021-12-18|website=www.hopkinsmedicine.org|date=26 November 2019 |language=en}}</ref>

Migraines are currently thought to be caused by dysfunction of the nerves in the brain.<ref name="uptodate">{{cite web | vauthors = Cutrer FM, Bajwa A, Sabhat M | title = Pathophysiology, clinical manifestations and diagnosis of migraine in adults. | work = UpToDate | veditors = Post TW | location = San Francisco, CA | publisher = Wolters Kluwer | access-date = 23 April 2014 | url = https://www.uptodate.com/contents/pathophysiology-clinical-manifestations-and-diagnosis-of-migraine-in-adults }}</ref> Previously, migraines were thought to be caused by a primary problem with the blood vessels in the brain.<ref>{{cite journal | vauthors = Goadsby PJ | title = The vascular theory of migraine--a great story wrecked by the facts | journal = Brain | volume = 132 | issue = Pt 1 | pages = 6–7 | date = January 2009 | pmid = 19098031 | doi = 10.1093/brain/awn321 | doi-access = free }}</ref> This vascular theory, which was developed in the 20th century by Wolff, suggested that the aura in [[migraines]] is caused by constriction of intracranial vessels (vessels inside the brain), and the headache itself is caused by rebound dilation of extracranial vessels (vessels just outside the brain). Dilation of these extracranial blood vessels activates the pain receptors in the surrounding nerves, causing a headache. The vascular theory is no longer accepted.<ref name="uptodate" /><ref name="Charles">{{cite journal | vauthors = Charles A | title = Vasodilation out of the picture as a cause of migraine headache | journal = The Lancet. Neurology | volume = 12 | issue = 5 | pages = 419–420 | date = May 2013 | pmid = 23578774 | doi = 10.1016/s1474-4422(13)70051-6 | s2cid = 42240966 }}</ref>  Studies have shown migraine head pain is not accompanied by extracranial vasodilation, but rather only has some mild intracranial vasodilation.<ref name="Amin">{{cite journal | vauthors = Amin FM, Asghar MS, Hougaard A, Hansen AE, Larsen VA, de Koning PJ, Larsson HB, Olesen J, Ashina M | title = Magnetic resonance angiography of intracranial and extracranial arteries in patients with spontaneous migraine without aura: a cross-sectional study | journal = The Lancet. Neurology | volume = 12 | issue = 5 | pages = 454–461 | date = May 2013 | pmid = 23578775 | doi = 10.1016/S1474-4422(13)70067-X | s2cid = 25553357 }}</ref>

Currently, most specialists think migraines are due to a primary problem with the nerves in the brain.<ref name="uptodate" /> Auras are thought to be caused by a wave of increased activity of neurons in the [[cerebral cortex]] (a part of the brain) known as cortical spreading depression<ref name="pmid11287655">{{cite journal | vauthors = Hadjikhani N, Sanchez Del Rio M, Wu O, Schwartz D, Bakker D, Fischl B, Kwong KK, Cutrer FM, Rosen BR, Tootell RB, Sorensen AG, Moskowitz MA | title = Mechanisms of migraine aura revealed by functional MRI in human visual cortex | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 98 | issue = 8 | pages = 4687–4692 | date = April 2001 | pmid = 11287655 | pmc = 31895 | doi = 10.1073/pnas.071582498 | doi-access = free | bibcode = 2001PNAS...98.4687H }}</ref> followed by a period of depressed activity.<ref>{{cite journal | vauthors = Buzzi MG, Moskowitz MA | title = The pathophysiology of migraine: year 2005 | journal = The Journal of Headache and Pain | volume = 6 | issue = 3 | pages = 105–111 | date = June 2005 | pmid = 16355290 | pmc = 3451639 | doi = 10.1007/s10194-005-0165-2 }}</ref> Some people think headaches are caused by the activation of [[sensory nerves]] which release peptides or [[serotonin]], causing inflammation in arteries, dura and  meninges and also cause some vasodilation. [[Triptan]]s, medications that treat migraines, block serotonin receptors and constrict blood vessels.<ref>{{cite book|chapter-url=http://accessmedicine.mhmedical.com/content.aspx?bookid=348&sectionid=40381638| vauthors = Denny CJ, Schull MJ | chapter = Chapter 159. Headache and Facial Pain. | veditors = Tintinalli JE, Stapczynski J, Ma O, Cline DM, Cydulka RK, Meckler GD | title = Tintinalli's Emergency Medicine: A Comprehensive Study Guide | edition = 7th | location = New York, NY | publisher = The McGraw-Hill Companies | date = 2011 |archive-url= https://web.archive.org/web/20150531030337/http://accessmedicine.mhmedical.com/content.aspx?bookid=348&sectionid=40381638 |archive-date=31 May 2015 |access-date=30 May 2015}}</ref>

People who are more susceptible to experiencing migraines without headaches are those who have a family history of migraines, women, and women who are experiencing hormonal changes or are taking [[birth control pills]] or are prescribed [[Hormone replacement therapy (menopause)|hormone replacement therapy]].<ref>{{cite web|title=Migraine Without Headache|url=http://www.neurobalancechiropractic.com.au/migraine-without-headache/|publisher=Neurobalance|access-date=16 July 2014|url-status=live|archive-url= https://web.archive.org/web/20150108113836/http://www.neurobalancechiropractic.com.au/migraine-without-headache/ |archive-date=8 January 2015}}</ref>

[[Tension headaches]] are thought to be caused by the activation of peripheral nerves in the head and neck muscles.<ref name="Loder">{{cite journal | vauthors = Loder E, Rizzoli P | title = Tension-type headache | journal = BMJ | volume = 336 | issue = 7635 | pages = 88–92 | date = January 2008 | pmid = 18187725 | pmc = 2190284 | doi = 10.1136/bmj.39412.705868.ad }}</ref>

[[Cluster headaches]] involve overactivation of the [[trigeminal nerve]] and [[hypothalamus]] in the brain, but the exact cause is unknown.<ref name="Leroux">{{cite journal | vauthors = Leroux E, Ducros A | title = Cluster headache | journal = Orphanet Journal of Rare Diseases | volume = 3 | issue = 1 | article-number = 20 | date = July 2008 | pmid = 18651939 | pmc = 2517059 | doi = 10.1186/1750-1172-3-20 | doi-access = free }}</ref><ref>{{Cite book |last=Levin |first=Emily Lehmann |title=Pain Neurosurgery |chapter-url=https://oxfordmedicine.com/view/10.1093/med/9780190887674.001.0001/med-9780190887674-chapter-16 |chapter=Cluster Headache |year=2019 |pages=125–130 |publisher=Oxford University Press |isbn=978-0-19-088770-4 |language=en-US |doi=10.1093/med/9780190887674.003.0016}}</ref>

== Diagnosis ==
{|border="1" class="wikitable"
|+ Differential diagnosis of headaches

![[Tension headache]]
![[New daily persistent headache]]
![[Cluster headache]]
![[Migraine]]
|-
| mild to moderate dull or aching pain||  || severe pain|| moderate to severe pain
|-
| duration of 30 minutes to several hours
|| duration of at least four hours daily
|| duration of 30 minutes to 3 hours
|| duration of 4 hours to 3 days
|-
|
|| Occur in periods of 15 days a month for three months
|| may happen multiple times in a day for months
|| periodic occurrence; several per month to several per year
|-
|located as tightness or pressure across head
|| located on one or both sides of the head
|| located one side of head focused at eye or [[Temple (anatomy)|temple]]
|| located on one or both sides of head
|-
|
|| consistent pain
|| pain describable as sharp or stabbing
|| pulsating or throbbing pain
|-
|no nausea or vomiting
||
||
||nausea, perhaps with vomiting
|-
| no [[Aura (symptom)|aura]]
||no aura
||
||auras
|-
|uncommonly, [[Photosensitivity in humans|light sensitivity]] or noise sensitivity
||
|| may be accompanied by [[running nose]], [[tears]], and [[Ptosis (eyelid)|drooping eyelid]], often only on one side
||sensitivity to movement, light, and noise
|-
|
|| exacerbated by regular use of [[acetaminophen]] or [[NSAIDS]]
||
|| may exist with tension headache<ref name="BBDtriptans">{{cite journal |journal=Consumer Reports Best Buy Drugs |date=March 2013 |title=Using the triptans to treat: Migraine headaches: Comparing effectiveness, safety, and price |page=8 |url=http://www.consumerreports.org/health/resources/pdf/best-buy-drugs/triptanFINAL.pdf |access-date=18 March 2013 |url-status=live |archive-url=https://web.archive.org/web/20130320142528/http://www.consumerreports.org/health/resources/pdf/best-buy-drugs/triptanFINAL.pdf |archive-date=20 March 2013 }}</ref>
|}

Most headaches can be diagnosed by the clinical history alone.<ref name=Goadsby /> If the symptoms described by the person sound dangerous, further testing with neuroimaging or lumbar puncture may be necessary. Electroencephalography (EEG) is not useful for headache diagnosis.<ref>{{cite journal | vauthors = Gronseth GS, Greenberg MK | title = The utility of the electroencephalogram in the evaluation of patients presenting with headache: a review of the literature | journal = Neurology | volume = 45 | issue = 7 | pages = 1263–1267 | date = July 1995 | pmid = 7617180 | doi = 10.1212/WNL.45.7.1263 | s2cid = 26022438 }}</ref>

The first step to diagnosing a headache is to determine if the headache is old or new.<ref name=Smetana /> A "new headache" can be a headache that has started recently, or a chronic headache that has changed character.<ref name=Smetana /> For example, if a person has chronic weekly headaches with pressure on both sides of his head, and then develops a sudden severe throbbing headache on one side of his head, they have a new headache.{{citation needed|date=June 2021}}

=== Red flags ===
It can be challenging to differentiate between low-risk, benign headaches and high-risk, dangerous headaches since symptoms are often similar.<ref name="Abrams Journal">{{cite journal | vauthors = Abrams BM | title = Factors that cause concern | journal = The Medical Clinics of North America | volume = 97 | issue = 2 | pages = 225–242 | date = March 2013 | pmid = 23419623 | doi = 10.1016/j.mcna.2012.11.002 }}</ref> Headaches that are possibly dangerous require further lab tests and imaging to diagnose.<ref name="Clinch" />

The American College for Emergency Physicians published criteria for low-risk headaches. They are as follows:<ref name="ACEP Criteria">{{cite journal | author = American College of Emergency Physicians | title = Clinical policy: critical issues in the evaluation and management of patients presenting to the emergency department with acute headache | journal = Annals of Emergency Medicine | volume = 39 | issue = 1 | pages = 108–122 | date = January 2002 | pmid = 11782746 | doi = 10.1067/mem.2002.120125 }}</ref>
* age younger than 30 years
* features typical of primary headache
* history of similar headache
* no abnormal findings on neurologic exam
* no concerning change in normal headache pattern
* no high-risk comorbid conditions (for example, HIV)
* no new concerning history or physical examination findings

A number of characteristics make it more likely that the headache is due to potentially dangerous secondary causes which may be life-threatening or cause long-term damage. These "red flag" symptoms mean that a headache warrants further investigation with neuroimaging and lab tests.<ref name="Clinch" />

In general, people complaining of their "first" or "worst" headache warrant imaging and further workup.<ref name="Clinch" /> People with progressively worsening headache also warrant imaging, as they may have a mass or a bleed that is gradually growing, pressing on surrounding structures and causing worsening pain.<ref name="Abrams Journal" /> People with neurological findings on exam, such as weakness, also need further workup.<ref name="Abrams Journal" />

The American Headache Society recommends using "SSNOOP", a mnemonic to remember the red flags for identifying a secondary headache:<ref name="Smetana">{{cite book | chapter-url = http://accessmedicine.mhmedical.com/content.aspx?bookid=500&sectionid=41026552 | vauthors = Smetana GW | chapter = Chapter 9. Headache. | veditors = Henderson MC, Tierney Jr LM, Smetana GW | title = The Patient History: An Evidence-Based Approach to Differential Diagnosis | location = New York, NY | publisher = McGraw-Hill | date = 2012 | archive-url = https://web.archive.org/web/20150531030403/http://accessmedicine.mhmedical.com/content.aspx?bookid=500&sectionid=41026552 |archive-date = 31 May 2015 }}</ref>
* Systemic symptoms (fever or weight loss)
* Systemic disease (HIV infection, malignancy)
* Neurologic symptoms or signs
* Onset sudden (thunderclap headache)
* Onset after age 40 years
* Previous headache history (first, worst, or different headache)

Other red flag symptoms include:<ref name="Clinch" /><ref name="Smetana" /><ref name="Abrams Journal" /><ref name="Hainer">{{cite journal | vauthors = Hainer BL, Matheson EM | title = Approach to acute headache in adults | journal = American Family Physician | volume = 87 | issue = 10 | pages = 682–687 | date = May 2013 | pmid = 23939446 }}</ref>
{|class="wikitable"
|-
! Red Flag !! Possible causes !! The reason why a red flag indicates possible causes !! Diagnostic tests
|-
| New headache after age 50 || Temporal arteritis, mass in brain || Temporal arteritis is an inflammation of vessels close to the temples in older people, which decreases blood flow to the brain and causes pain. May also have tenderness in temples or jaw claudication. Some brain cancers are more common in older people. || Erythrocyte sedimentation rate (diagnostic test for temporal arteritis), neuroimaging
|-
| Very sudden onset headache ([[thunderclap headache]]) || Brain bleed ([[subarachnoid hemorrhage]], hemorrhage into mass lesion, [[vascular malformation]]), [[pituitary apoplexy]], mass (especially in [[Posterior cranial fossa|posterior fossa]]) || A bleed in the brain irritates the meninges which causes pain. Pituitary apoplexy (bleeding or impaired blood supply to the pituitary gland at the base of the brain) is often accompanied by double vision or visual field defects, since the pituitary gland is right next to the [[optic chiasm]] (eye nerves). || [[Neuroimaging]], [[lumbar puncture]] if computed tomography is negative
|-
| Headaches increasing in frequency and severity || Mass, subdural hematoma, medication overuse || As a brain mass gets larger, or a [[subdural hematoma]] (blood outside the vessels underneath the [[Dura mater|dura]]) it pushes more on surrounding structures causing pain. Medication overuse headaches worsen with more medication taken over time. || Neuroimaging, drug screen
|-
| New onset headache in a person with possible HIV or cancer || [[Meningitis]] (chronic or carcinomatous), [[brain abscess]] including [[toxoplasmosis]], [[metastasis]] || People with HIV or cancer are immunosuppressed so are likely to get infections of the meninges or infections in the brain causing abscesses. Cancer can metastasize, or travel through the blood or lymph to other sites in the body. || Neuroimaging, lumbar puncture if neuroimaging is negative
|-
| Headache with signs of total body illness (fever, stiff neck, rash) || [[Meningitis]], [[encephalitis]] (inflammation of the brain tissue), [[Lyme disease]], [[collagen vascular disease]] || A stiff neck, or inability to flex the neck due to pain, indicates inflammation of the meninges. Other signs of systemic illness indicates infection. || Neuroimaging, lumbar puncture, serology (diagnostic blood tests for infections)
|-
| [[Papilledema]] || Brain mass, [[benign intracranial hypertension]] (pseudotumor cerebri), [[meningitis]] || Increased intracranial pressure pushes on the eyes (from inside the brain) and causes papilledema. || Neuroimaging, lumbar puncture
|-
| Severe headache following head trauma || Brain bleeds ([[intracranial hemorrhage]], [[subdural hematoma]], [[epidural hematoma]]), post-traumatic headache || Trauma can cause bleeding in the brain or shake the nerves, causing a post-traumatic headache || Neuroimaging of brain, skull, and possibly cervical spine
|-
| Inability to move a limb || Arteriovenous malformation, collagen vascular disease, intracranial mass lesion || Focal neurological signs indicate something is pushing against nerves in the brain responsible for one part of the body || Neuroimaging, blood tests for collagen vascular diseases
|-
| Change in personality, consciousness, or mental status || [[Central nervous system infection]], [[Intracranial bleeding|intracranial bleed]], mass || Change in mental status indicates a global infection or inflammation of the brain, or a large bleed compressing the brainstem where the consciousness centers lie || Blood tests, lumbar puncture, neuroimaging
|-
| Headache triggered by cough, exertion or while engaged in sexual intercourse || Mass lesion, subarachnoid hemorrhage || Coughing and exertion increases the intra cranial pressure, which may cause a vessel to burst, causing a subarachnoid hemorrhage. A mass lesion already increases intracranial pressure, so an additional increase in intracranial pressure from coughing etc. will cause pain. || Neuroimaging, lumbar puncture
|-
|}

=== Old headaches ===
Old headaches are usually primary headaches and are not dangerous. They are most often caused by [[migraines]] or [[tension headaches]]. Migraines are often unilateral, pulsing headaches accompanied by nausea or vomiting. There may be an aura (visual symptoms, numbness or tingling) 30–60 minutes before the headache, warning the person of a headache. Migraines may also not have auras.<ref name=Hainer /> Tension-type headaches usually have bilateral "bandlike" pressure on both sides of the head usually without nausea or vomiting. However, some symptoms from both headache groups may overlap. It is important to distinguish between the two because the treatments are different.<ref name=Hainer />

The mnemonic 'POUND' helps distinguish between migraines and tension-type headaches. POUND stands for: {{bulleted list|Pulsatile quality of headache|One-day duration (four to 72 hours)|Unilateral location|Nausea or vomiting|Disabling intensity<ref>{{cite journal | vauthors = Gilmore B, Michael M | title = Treatment of acute migraine headache | journal = American Family Physician | volume = 83 | issue = 3 | pages = 271–280 | date = February 2011 | pmid = 21302868 | url = https://www.aafp.org/afp/2011/0201/p271.html | access-date = 15 September 2021 }}</ref> }}

One review article found that if 4–5 of the POUND characteristics are present, a migraine is 24 times as likely a diagnosis than a tension-type headache ([[Likelihood ratios in diagnostic testing|likelihood ratio]] 24). If 3 characteristics of POUND are present, migraine is 3 times more likely a diagnosis than tension type headache ([[Likelihood ratios in diagnostic testing|likelihood ratio]] 3).<ref name=Detsky /> If only 2 POUND characteristics are present, tension-type headaches are 60% more likely (likelihood ratio 0.41). Another study found the following factors independently each increase the chance of migraine over tension-type headache: nausea, photophobia, phonophobia, exacerbation by physical activity, unilateral, throbbing quality, chocolate as a headache trigger, and cheese as a headache trigger.<ref name="Smetana 2">{{cite journal | vauthors = Smetana GW | title = The diagnostic value of historical features in primary headache syndromes: a comprehensive review | journal = Archives of Internal Medicine | volume = 160 | issue = 18 | pages = 2729–2737 | date = October 2000 | pmid = 11025782 | doi = 10.1001/archinte.160.18.2729 | doi-access = free }}</ref>

[[Cluster headaches]] are relatively rare (1 in 1000 people) and are more common in men than women.<ref>{{cite book|title=Harrison's Principles of Internal Medicine|date=8 April 2015|publisher=McGraw-Hill Education|isbn=978-0-07-180215-4 |pages=2594–2595|edition=19th}}</ref> They present with sudden onset explosive pain around one eye and are accompanied by autonomic symptoms (tearing, runny nose and red eye).<ref name=Goadsby />

[[Temporomandibular joint dysfunction|Temporomandibular jaw pain]] (chronic pain in the jaw joint), and [[cervicogenic headache]] (headache caused by pain in muscles of the neck) are also possible diagnoses.<ref name=Smetana />

For chronic, unexplained headaches, keeping a headache diary can be useful for tracking symptoms and identifying triggers, such as association with menstrual cycle, exercise and food. While mobile electronic diaries for smartphones are becoming increasingly common, a recent review found most are developed with a lack of evidence base and scientific expertise.<ref name="pmid25138438">{{cite journal | vauthors = Hundert AS, Huguet A, McGrath PJ, Stinson JN, Wheaton M | title = Commercially available mobile phone headache diary apps: a systematic review | journal = JMIR mHealth and uHealth | volume = 2 | issue = 3 | pages = e36 | date = August 2014 | pmid = 25138438 | pmc = 4147710 | doi = 10.2196/mhealth.3452 | doi-access = free }}</ref>

[[Cephalalgiaphobia]] is fear of headaches or getting a headache.

=== New headaches ===
New headaches are more likely to be dangerous [[#Secondary headaches|secondary headaches]]. They can, however, simply be the first presentation of a chronic headache syndrome, like [[migraine]] or a [[tension headache]].

One recommended diagnostic approach is as follows.<ref>{{cite book | chapter-url = http://accessmedicine.mhmedical.com/content.aspx?bookid=383&sectionid=41676347 | chapter = Chapter 18: I Have a Patient with Headache. How Do I Determine the Cause? | veditors = Stern SC, Cifu AS, Altkorn D | title = Symptom to Diagnosis: An Evidence-Based Guide | edition = 2nd | location = New York, NY | publisher = McGraw-Hill | date = 2010 | archive-url = https://web.archive.org/web/20150531030350/http://accessmedicine.mhmedical.com/content.aspx?bookid=383&sectionid=41676347 | archive-date=31 May 2015 }}</ref> If any urgent [[#Red flags|red flags]] are present such as [[visual impairment]], new [[Seizure|seizures]], new [[weakness]], or new [[confusion]], further workup with imaging and possibly a [[lumbar puncture]] should be done (see red flags section for more details). If the headache is sudden onset (thunderclap headache), a [[CT scan|computed tomography scan]] (CT scan) to look for a brain bleed ([[subarachnoid hemorrhage]]) should be done. If the CT scan does not show a bleed, a lumbar puncture should be done to look for blood in the [[cerebrospinal fluid]] (CSF), as the CT scan can be [[False positives and false negatives|falsely negative]] and [[Subarachnoid hemorrhage|subarachnoid hemorrhages]] can be fatal. If there are signs of infection such as [[fever]], [[rash]], or [[Neck stiffness|stiff neck]], a lumbar puncture to look for [[meningitis]] should be considered. In an older person, if there is [[jaw claudication]] and scalp [[Tenderness (medicine)|tenderness]], a temporal artery biopsy should be performed to look for temporal [[arteritis]], immediate treatment should be started, if results of the biopsy are positive.{{citation needed|date=June 2021}}

=== Neuroimaging ===

==== Old headaches ====
The US Headache Consortium has guidelines for neuroimaging of non-acute headaches.<ref>{{cite book | vauthors = Frishberg BM, Rosenberg JH, Matchar DB, McCrory DC, Pietrzak MP, Rozen TD, Silberstein SD | title = Evidence-based guidelines in the primary care setting: neuroimaging in patients with nonacute headache. | location = St Paul, MN | publisher = US Headache Consortium | date = April 2000 | pages = 1–25 | citeseerx = 10.1.1.565.1524 }}</ref> Most old, chronic headaches do not require neuroimaging. If a person has the characteristic symptoms of a migraine, neuroimaging is not needed as it is very unlikely the person has an intracranial abnormality.<ref name="AHSfive">{{cite web |author1=American Headache Society |author1-link=American Headache Society |date=September 2013 |title=Five Things Physicians and Patients Should Question |publisher=[[American Headache Society]] |work=[[Choosing Wisely]] |url=http://www.choosingwisely.org/doctor-patient-lists/american-headache-society/ |access-date=10 December 2013 |archive-url=https://web.archive.org/web/20131206060123/http://www.choosingwisely.org/doctor-patient-lists/american-headache-society/ |archive-date=6 December 2013 }}, which cites
* {{cite journal | vauthors = Lewis DW, Dorbad D | title = The utility of neuroimaging in the evaluation of children with migraine or chronic daily headache who have normal neurological examinations | journal = Headache | volume = 40 | issue = 8 | pages = 629–632 | date = September 2000 | pmid = 10971658 | doi = 10.1046/j.1526-4610.2000.040008629.x | s2cid = 14443890 }}
* {{cite journal | vauthors = Silberstein SD | title = Practice parameter: evidence-based guidelines for migraine headache (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology | journal = Neurology | volume = 55 | issue = 6 | pages = 754–762 | date = September 2000 | pmid = 10993991 | doi = 10.1212/WNL.55.6.754 | doi-access = free }}
* {{cite journal | author = Medical Advisory Secretariat | title = Neuroimaging for the evaluation of chronic headaches: an evidence-based analysis | journal = Ontario Health Technology Assessment Series | volume = 10 | issue = 26 | pages = 1–57 | year = 2010 | pmid = 23074404 | pmc = 3377587 }}</ref> If the person has neurological findings, such as weakness, on exam, neuroimaging may be considered.{{citation needed|date=June 2021}}

==== New headaches ====
All people who present with [[#Red flags|red flags]] indicating a dangerous secondary headache should receive neuroimaging.<ref name=Hainer /> The best form of neuroimaging for these headaches is controversial.<ref name=Clinch /> Non-contrast computerized tomography (CT) scan is usually the first step in head imaging as it is readily available in Emergency Departments and hospitals and is cheaper than MRI. Non-contrast CT is best for identifying an acute head bleed. Magnetic Resonance Imaging (MRI) is best for brain tumors and [[Posterior fossa malformations–hemangiomas–arterial anomalies–cardiac defects–eye abnormalities–sternal cleft and supraumbilical raphe syndrome|problems in the posterior fossa]], or back of the brain.<ref name=Clinch /> MRI is more sensitive for identifying intracranial problems, however it can pick up brain abnormalities that are not relevant to the person's headaches.<ref name=Clinch />

The American College of Radiology recommends the following imaging tests for different specific situations:<ref name="Strain_2000">{{cite journal | vauthors = Strain JD, Strife JL, Kushner DC, Babcock DS, Cohen HL, Gelfand MJ, Hernandez RJ, McAlister WH, Parker BR, Royal SA, Slovis TL, Smith WL, Rothner AD | title = Headache. American College of Radiology. ACR Appropriateness Criteria | journal = Radiology | volume = 215 | issue = Suppl | pages = 855–60 | date = June 2000 | pmid = 11037510 | doi = | url = }}</ref>

{|class="wikitable"
|-
! Clinical Features !! Recommended neuroimaging test
|-
| Headache in immunocompromised people (cancer, HIV) || [[MRI]] of head with or without contrast
|-
| Headache in people older than 60 with suspected temporal arteritis || MRI of head with or without contrast
|-
| Headache with suspected meningitis || CT or MRI without contrast
|-
| Severe headache in pregnancy || CT or MRI without contrast
|-
| Severe unilateral headache caused by possible dissection of carotid or arterial arteries || MRI of head with or without contrast, [[magnetic resonance angiography]] or [[Computed tomography angiography|Computed Tomography Angiography]] of head and neck.
|-
| Sudden onset headache or worst headache of life || CT of head without contrast, [[Computed tomography angiography|Computed Tomography Angiography]] of head and neck with contrast, [[magnetic resonance angiography]] of head and neck with and without contrast, MRI of head without contrast
|}

==== Lumbar puncture ====
A [[lumbar puncture]] is a procedure in which cerebral spinal fluid is removed from the spine with a needle. A lumbar puncture is necessary to look for infection or blood in the spinal fluid. A lumbar puncture can also evaluate the pressure in the spinal column, which can be useful for people with [[idiopathic intracranial hypertension]] (usually young, obese women who have increased intracranial pressure), or other causes of increased intracranial pressure. In most cases, a CT scan should be done first.<ref name=Goadsby />

=== Classification ===
Headaches are most thoroughly classified by the [[International Headache Society]]'s International Classification of Headache Disorders (ICHD), which published the second edition in 2004.<ref name="IHS_ICHD2">{{cite book |url=http://ihs-classification.org/en/ |title=IHS Classification ICHD-2 |publisher=International Headache Society |edition=Online |archive-url=https://web.archive.org/web/20131103104037/http://ihs-classification.org/en/ |archive-date=3 November 2013 |access-date=18 November 2013 }}</ref> The third edition of the International Headache Classification was published in 2013 in a beta version ahead of the final version.<ref>[//www.ichd-3.org/ ''Website The International Headache Classification (ICHD-3 Beta)'']. Retrieved 29. August 2016.</ref> This classification is accepted by the [[WHO]].{{sfn|Olesen et al.|2005|pages=9–11}}

Other classification systems exist.  One of the first published attempts was in 1951.<ref>{{cite journal | vauthors = Brown MR | title = The classification and treatment of headache | journal = The Medical Clinics of North America | volume = 35 | issue = 5 | pages = 1485–1493 | date = September 1951 | pmid = 14862569 | doi = 10.1016/S0025-7125(16)35236-1 }}</ref> The US [[National Institutes of Health]] developed a classification system in 1962.<ref>{{cite journal | journal = JAMA | author = Ad Hoc Committee on Classification of Headache | title = Classification of Headache | volume = 179 | pages = 717–8 | year = 1962 | doi = 10.1001/jama.1962.03050090045008 | issue = 9 }}</ref>

==== ICHD-2 ====
{{Main|International Classification of Headache Disorders}}
The [[International Classification of Headache Disorders]] (ICHD) is an in-depth hierarchical classification of headaches published by the [[International Headache Society]]. It contains explicit (operational) [[diagnostic criteria]] for headache disorders. The first version of the classification, ICHD-1, was published in 1988. The current revision, ICHD-2, was published in 2004.<ref>{{cite book |title=The Headaches |edition=3 |publisher=[[Lippincott Williams & Wilkins]] |year=2005  | vauthors = Olesen PJ, Goadsby NM, Ramadan P, Tfelt-Hansen KM, Welch |ref={{Harvid|Olesen et al.|2005}}}}</ref> The classification uses numeric codes. The top, one-digit diagnostic level includes 14 headache groups. The first four of these are classified as primary headaches, groups 5-12 as secondary headaches, [[Human cranium|cranial]] [[neuralgia]], central and primary facial pain and other headaches for the last two groups.<ref>{{cite book |title=Comprehensive Review of Headache Medicine |publisher=[[Oxford University Press]] |year=2008| isbn=978-0-19-536673-0 | vauthors = Levin M, Baskin SM, Bigal ME |ref={{Harvid|Levin et al.|2008}}}}</ref>

The ICHD-2 classification defines [[migraine]]s, tension-types headaches, cluster headache and other [[trigeminal]] autonomic headache as the main types of primary headaches.<ref name="IHS_ICHD2" /> Also, according to the same classification, stabbing headaches and headaches due to [[cough]], exertion and sexual activity ([[sexual headache]]) are classified as primary headaches. The daily-persistent headaches along with the hypnic headache and thunderclap headaches are considered primary headaches as well.<ref>{{cite book | vauthors = Linn FH | title = Headache | chapter = Primary thunderclap headache | volume = 97 | pages = 473–481 | date = 2010 | pmid = 20816448 | doi = 10.1016/s0072-9752(10)97042-5 | publisher = Elsevier | isbn = 978-0-444-52139-2 | series = Handbook of Clinical Neurology }}</ref><ref>{{cite journal | vauthors = Obermann M, Holle D | title = Hypnic headache | journal = Expert Review of Neurotherapeutics | volume = 10 | issue = 9 | pages = 1391–1397 | date = September 2010 | pmid = 20839413 | doi = 10.1586/ern.10.112 | s2cid = 19141493 }}</ref>

Secondary headaches are classified based on their cause and not on their [[symptoms]].<ref name="IHS_ICHD2" /> According to the ICHD-2 classification, the main types of secondary headaches include those that are due to head or neck trauma such as [[Whiplash (medicine)|whiplash injury]], [[intracranial hematoma]], post [[craniotomy]] or other head or neck injury. Headaches caused by cranial or cervical vascular disorders such as [[Stroke#Ischemic stroke|ischemic stroke]] and [[transient ischemic attack]], non-traumatic intracranial hemorrhage, [[Cerebral arteriovenous malformation|vascular malformations]] or [[arteritis]] are also defined as secondary headaches. This type of headache may also be caused by [[cerebral venous thrombosis]] or different intracranial vascular disorders. Other secondary headaches are those due to intracranial disorders that are not vascular such as low or high pressure of the cerebrospinal fluid pressure, non-infectious inflammatory disease, intracranial neoplasm, [[epileptic seizure]] or other types of disorders or diseases that are intracranial but that are not associated with the vasculature of the [[central nervous system]].{{citation needed|date=June 2021}}

ICHD-2 classifies headaches that are caused by the ingestion of a certain substance or by its withdrawal as secondary headaches as well. This type of headache may result from the overuse of some medications or exposure to some substances. [[HIV]]/[[AIDS]], intracranial [[infections]] and systemic infections may also cause secondary headaches. The ICHD-2 system of classification includes the headaches associated with homeostasis disorders in the category of secondary headaches. This means that headaches caused by [[Kidney dialysis|dialysis]], [[high blood pressure]], [[hypothyroidism]], cephalalgia and even [[fasting]] are considered secondary headaches. Secondary headaches, according to the same classification system, can also be due to the injury of any of the facial structures including [[teeth]], jaws, or [[temporomandibular joint]]. Headaches caused by psychiatric disorders such as [[somatization]] or [[psychotic disorders]] are also classified as secondary headaches.{{citation needed|date=June 2021}}

The ICHD-2 classification puts cranial neuralgias and other types of [[neuralgia]] in a different category. According to this system, there are 19 types of neuralgias and headaches due to different central causes of facial pain. Moreover, the ICHD-2 includes a category that contains all the headaches that cannot be classified.{{citation needed|date=June 2021}}

Although the ICHD-2 is the most complete headache classification there is and it includes frequency in the diagnostic criteria of some types of headaches (primarily primary headaches), it does not specifically code frequency or severity which are left at the discretion of the examiner.<ref name="IHS_ICHD2" />

==== NIH ====
{{Main|NIH classification of headaches}}
The NIH classification consists of brief definitions of a limited number of headaches.{{sfn|Levin et al.|2008|page=60}}

The NIH system of classification is more succinct and only describes five categories of headaches. In this case, primary headaches are those that do not show organic or structural causes. According to this classification, primary headaches can only be vascular, [[myogenic]], cervicogenic, traction, and inflammatory.<ref>{{Cite web|title=Headache Information Page {{!}} National Institute of Neurological Disorders and Stroke|url=https://www.ninds.nih.gov/health-information/disorders/headache|access-date=21 July 2021|website=www.ninds.nih.gov}}</ref>

== Management ==
[[File:Image-Lottie Collins sings and dances to the tunes of Ta-Ra-Ra Boom-de-ay in a Bromo-Seltzer ad.jpg|thumb|An old advertisement for a headache medicine]]
{{See also|Management of chronic headaches}}
Primary headache syndromes have many different possible treatments. In those with chronic headaches the long term use of opioids appears to result in greater harm than benefit.<ref>{{cite journal | vauthors = Franklin GM | title = Opioids for chronic noncancer pain: a position paper of the American Academy of Neurology | journal = Neurology | volume = 83 | issue = 14 | pages = 1277–1284 | date = September 2014 | pmid = 25267983 | doi = 10.1212/WNL.0000000000000839 | doi-access = free }}</ref>

=== Secondary headaches (caused by another disease) ===
Treatment of secondary headaches involves treating their underlying cause. For example, a person with meningitis will require antibiotics, and a person with a [[brain tumor]] may require surgery, [[chemotherapy]] or brain radiation. The [[#Secondary|possible origins of a headache]] have been studied and classified.

=== Migraines ===

{{Main|Management of migraine}}

Migraines can be somewhat improved by lifestyle changes, but most people require medicines to control their symptoms.<ref name=Goadsby /> Medications are either to prevent getting migraines, or to reduce symptoms once a migraine starts.{{citation needed|date=June 2021}}

Preventive medications are generally recommended when people have more than four attacks of migraine per month, headaches last longer than 12 hours or the headaches are very disabling.<ref name=Goadsby /><ref name="UTD Migraine Tx">{{cite report | vauthors = Bajwa ZH, Sabahat A | title = Preventive Treatment of Migraine in Adults. | work = UptoDate | veditors = Swanson JW | location = San Francisco, CA. | publisher = Wolters Kluwer <!-- }}</ref> Possible therapies include beta blockers, antidepressants, anticonvulsants and NSAIDs.<ref name="UTD Migraine Tx" /> The type of preventive medicine is usually chosen based on the other symptoms the person has. For example, if the person also has depression, an antidepressant is a good choice.{{citation needed|date=June 2021}}

Rescue (also known as abortive) treatment for migraines may be [[Oral administration|oral]] or [[Sublingual administration|sublingual (under the tongue)]] if the migraine is mild to moderate; if more severe, [[Intravenous therapy|intravenous]], [[Rectal (medicine)|rectal]], or [[Intramuscular injection|intramuscular]] administration may be needed. Mild to moderate headaches should first be treated with [[acetaminophen]] (paracetamol) or NSAIDs, like [[ibuprofen]]. If accompanied by nausea or vomiting, an antiemetic such as [[Metoclopramide|metoclopramide (Reglan)]] can be given orally or rectally. Moderate to severe attacks should be treated first with an oral [[triptans|triptan]], a medication that mimics [[serotonin]] (an [[agonist]]) and causes mild [[vasoconstriction]]. If accompanied by nausea and vomiting, parenteral (through a needle in the skin) triptans and antiemetics can be given.<ref>{{cite journal | vauthors = Láinez MJ, García-Casado A, Gascón F | title = Optimal management of severe nausea and vomiting in migraine: improving patient outcomes | journal = Patient Related Outcome Measures | volume = 4 | pages = 61–73 | date = October 2013 | pmid = 24143125 | pmc = 3798203 | doi = 10.2147/PROM.S31392 | doi-access = free }}</ref>

Sphenopalatine ganglion block (SPG block, also known nasal ganglion block or [[pterygopalatine ganglion]] blocks) can abort and prevent migraines, tension headaches and cluster headaches. It was originally described by American ENT surgeon Greenfield Sluder in 1908. Both blocks and neurostimulation have been studied as treatment for headaches.<ref>{{cite journal | vauthors = Boss KW, Przkora R, Kumar S | title = Sphenopalatine ganglion: block, radiofrequency ablation and neurostimulation - a systematic review | journal = The Journal of Headache and Pain | volume = 18 | issue = 1 | article-number = 118 | date = December 2017 | pmid = 29285576 | pmc = 5745368 | doi = 10.1186/s10194-017-0826-y | doi-access = free }}</ref>

Several complementary and alternative strategies can help with migraines. The American Academy of Neurology guidelines for migraine treatment in 2000 stated [[relaxation training]], electromyographic feedback and [[cognitive behavioral therapy]] may be considered for migraine treatment, along with medications.<ref>{{cite journal | vauthors = Silberstein SD | title = Practice parameter: evidence-based guidelines for migraine headache (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology | journal = Neurology | volume = 55 | issue = 6 | pages = 754–762 | date = September 2000 | pmid = 10993991 | doi = 10.1212/wnl.55.6.754 | doi-access = free }}</ref>

=== Tension-type headaches ===
[[Tension-type headache]]s can usually be managed with [[NSAIDs]] (such as [[ibuprofen]] and [[aspirin]]) an/or [[acetaminophen]].<ref name=Goadsby /> [[Triptans]] are not helpful in tension-type headaches unless the person also has migraines. For chronic tension type headaches, [[amitriptyline]] is the only medication proven to help.<ref name=Goadsby /><ref name="UpToDate Tension">{{cite web | vauthors = Taylor R | title = Tension type headaches in adults: Preventive treatment. | work = UpToDate | veditors = Swanson JW | publisher = Wolters Kluwer | location = San Francisco, CA | access-date = 24 April 2014 | url = https://www.uptodate.com/contents/tension-type-headache-in-adulfts-acute-treatment }}</ref><ref name="Amitryptiline">{{cite journal | vauthors = Jackson JL, Shimeall W, Sessums L, Dezee KJ, Becher D, Diemer M, Berbano E, O'Malley PG | title = Tricyclic antidepressants and headaches: systematic review and meta-analysis | journal = BMJ | volume = 341 | article-number = c5222 | date = October 2010 | pmid = 20961988 | pmc = 2958257 | doi = 10.1136/bmj.c5222 }}</ref> [[Amitriptyline]] is a medication which treats depression and also independently treats pain. It works by blocking the reuptake of [[serotonin]] and norepinephrine, and also reduces muscle tenderness by a separate mechanism.<ref name="UpToDate Tension" /> Studies evaluating acupuncture for tension-type headaches have been mixed.<ref name="pmid18499526">{{cite journal | vauthors = Davis MA, Kononowech RW, Rolin SA, Spierings EL | title = Acupuncture for tension-type headache: a meta-analysis of randomized, controlled trials | journal = The Journal of Pain | volume = 9 | issue = 8 | pages = 667–677 | date = August 2008 | pmid = 18499526 | doi = 10.1016/j.jpain.2008.03.011 | doi-access = free }}</ref><ref name="pmid27092807">{{cite journal | vauthors = Linde K, Allais G, Brinkhaus B, Fei Y, Mehring M, Shin BC, Vickers A, White AR | title = Acupuncture for the prevention of tension-type headache | journal = The Cochrane Database of Systematic Reviews | volume = 4 | issue = 8| article-number = CD007587 | date = April 2016 | pmid = 27092807 | pmc = 4955729 | doi = 10.1002/14651858.CD007587.pub2 }}</ref><ref name="pmid23075410">{{cite journal | vauthors = Hao XA, Xue CC, Dong L, Zheng Z | title = Factors associated with conflicting findings on acupuncture for tension-type headache: qualitative and quantitative analyses | journal = Journal of Alternative and Complementary Medicine | volume = 19 | issue = 4 | pages = 285–297 | date = April 2013 | pmid = 23075410 | doi = 10.1089/act.2013.19608 }}</ref><ref name="pmid16430123">{{cite journal | vauthors = Melchart D, Streng A, Hoppe A, Brinkhaus B, Becker-Witt C, Hammes M, Irnich D, Hummelsberger J, Willich SN, Linde K | title = The acupuncture randomised trial (ART) for tension-type headache--details of the treatment | journal = Acupuncture in Medicine | volume = 23 | issue = 4 | pages = 157–165 | date = December 2005 | pmid = 16430123 | doi = 10.1136/aim.23.4.157 | s2cid = 23437975 }}</ref><ref>{{cite journal | vauthors = Melchart D, Streng A, Hoppe A, Brinkhaus B, Witt C, Wagenpfeil S, Pfaffenrath V, Hammes M, Hummelsberger J, Irnich D, Weidenhammer W, Willich SN, Linde K | title = Acupuncture in patients with tension-type headache: randomised controlled trial | journal = BMJ | volume = 331 | issue = 7513 | pages = 376–382 | date = August 2005 | pmid = 16055451 | pmc = 1184247 | doi = 10.1136/bmj.38512.405440.8f }}</ref> Overall, they show that acupuncture is probably not helpful for tension-type headaches.

=== Cluster headaches ===
[[Therapy|Abortive therapy]] for cluster headaches includes subcutaneous sumatriptan (injected under the skin) and triptan nasal sprays. High flow oxygen therapy also helps with relief.<ref name=Goadsby />

For people with extended periods of cluster headaches, preventive therapy can be necessary. Verapamil is recommended as first line treatment. Lithium can also be useful. For people with shorter bouts, a short course of prednisone (10 days) can be helpful. Ergotamine is useful if given 1–2 hours before an attack.<ref name=Goadsby />

=== Neuromodulation ===
Peripheral neuromodulation has tentative benefits in primary headaches including cluster headaches and chronic migraine.<ref name=Reed2013>{{cite journal | vauthors = Reed KL | title = Peripheral neuromodulation and headaches: history, clinical approach, and considerations on underlying mechanisms | journal = Current Pain and Headache Reports | volume = 17 | issue = 1 | article-number = 305 | date = January 2013 | pmid = 23274677 | pmc = 3548086 | doi = 10.1007/s11916-012-0305-8 }}</ref> How it may work is still being looked into.<ref name=Reed2013/>

== Epidemiology ==
[[Literature review]]s find that approximately 64–77% of adults have had a headache at some point in their lives.<ref name="Manzoni" /><ref name="Stovner" />  During each year, on average, 46–53% of people have headaches.<ref name="Manzoni">{{cite book | vauthors = Manzoni GC, Stovner LJ | title = Headache | chapter = Epidemiology of headache | volume = 97 | pages = 3–22 | year = 2010 | pmid = 20816407 | doi = 10.1016/s0072-9752(10)97001-2 | isbn = 978-0-444-52139-2 | series = Handbook of Clinical Neurology | quote = [T]he prevalence [of headache within the last year] was on average 46% based on 35 different studies from all over the world, but the variation was immense, between 1% and 87%. The lifetime prevalence was much as expected – 64%, varying between 8% and 96% in 14 studies. For current chronic headache, the average of 10 studies was 3.4%, varying between 1.7% and 7.3%. }}</ref><ref name="Stovner">{{cite journal | vauthors = Stovner LJ, Andree C | title = Prevalence of headache in Europe: a review for the Eurolight project | journal = The Journal of Headache and Pain | volume = 11 | issue = 4 | pages = 289–299 | date = August 2010 | pmid = 20473702 | pmc = 2917556 | doi = 10.1007/s10194-010-0217-0 | quote = Calculating the mean of all the studies comprising more than 205,000 adult participants, current headache [i.e. headache within the last year] occurred in 53% of adults (61% among women and 45% among men).... The total lifetime prevalence of headache among adults was as expected higher than that of current headache (77%). }}</ref> However, the [[prevalence]] of headache varies widely depending on how the survey was conducted, with studies finding lifetime prevalence of as low as 8% to as high as 96%.<ref name="Manzoni" /><ref name="Stovner" /><ref>{{cite journal | vauthors = Stovner LJ, Hagen K, Jensen R, Katsarava Z, Lipton R, Scher A, Steiner T, Zwart JA | title = The global burden of headache: a documentation of headache prevalence and disability worldwide | journal = Cephalalgia | volume = 27 | issue = 3 | pages = 193–210 | date = March 2007 | pmid = 17381554 | doi = 10.1111/j.1468-2982.2007.01288.x | s2cid = 23927368 }}</ref>  Most of these headaches are not dangerous. Only approximately 1–5% of people who seek emergency treatment for headaches have a serious underlying cause.<ref>{{cite book | vauthors = Mattu M, Goyal D, Barrett JW, Broder J, DeAngelis M, Deblieux P, Garmel GM, Harrigan R, Karras D, L'Italien A, Manthey D |title=Emergency medicine: Avoiding the pitfalls and improving the outcomes |publisher=[[Wiley-Blackwell|Blackwell / BMJ Books]] |location=Malden, MA |year=2007 |page=39 |isbn=978-1-4051-4166-6}}</ref>

More than 90% of headaches are primary headaches.<ref name="D">{{cite web | vauthors = Kunkel RS |date=1 August 2010 |work=Disease Management Project: Publications |publisher=[[Cleveland Clinic]] |url= http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/neurology/headache-syndromes/ |title=Headache |access-date=6 August 2010 |url-status=live |archive-url= https://web.archive.org/web/20130504085702/http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/neurology/headache-syndromes/ |archive-date=4 May 2013 }}</ref> Most of these primary headaches are tension headaches.<ref name=Stovner /> Most people with tension headaches have "episodic" tension headaches that come and go. Only 3.3% of adults have chronic tension headaches, with headaches for more than 15 days in a month.<ref name=Stovner />

Approximately 12–18% of people in the world have migraines.<ref name=Stovner /> More women than men experience migraines. In Europe and North America, 5–9% of men experience migraines, while 12–25% of women experience migraines.<ref name=Manzoni />

Cluster headaches are relatively uncommon. They affect only 1–3 per thousand people in the world. Cluster headaches affect approximately three times as many men as women.<ref name=Stovner />

== History ==
[[File:Cruikshank - The Head Ache.png|thumb|upright=1.3|An 1819 caricature by [[George Cruikshank]] depicting a headache]]
The first recorded classification system was published by [[Aretaeus of Cappadocia]], a medical scholar of Greco-Roman [[Age of the Earth|antiquity]]. He made a distinction between three different types of headache: i) cephalalgia, by which he indicates a sudden onset, temporary headache; ii) cephalea, referring to a chronic type of headache; and iii) heterocrania, a paroxysmal headache on one side of the head.
Another classification system that resembles the modern ones was published by [[Thomas Willis]], in ''De Cephalalgia'' in 1672. In 1787 [[Christian Baur]] generally divided headaches into [[idiopathic]] (primary headaches) and [[symptomatic]] (secondary ones), and defined 84 categories.{{sfn|Levin et al.|2008|page=60}}

== Children ==
In general, children experience the same types of headaches as adults do, but their symptoms may be slightly different. The diagnostic approach to headaches in children is similar to that of adults. However, young children may not be able to verbalize pain well.<ref>{{cite journal | vauthors = Rothner AD | title = The evaluation of headaches in children and adolescents | journal = Seminars in Pediatric Neurology | volume = 2 | issue = 2 | pages = 109–118 | date = June 1995 | pmid = 9422238 | doi = 10.1016/s1071-9091(05)80021-x }}</ref> If a young child is fussy, they may have a headache.<ref name="Schultz">{{cite book | vauthors=Schultz BE, Macias CG | chapter=130: Headaches in Children | veditors=Tintinalli JE, Stapczynski J, Ma O, Cline DM, Cydulka RK, Meckler GD | title=Tintinalli's Emergency Medicine: A Comprehensive Study Guide | edition=7th | location=New York, NY | publisher=McGraw-Hill | year=2011 | chapter-url=http://accessmedicine.mhmedical.com/content.aspx?bookid=348&Sectionid=40381603 | url-status=live | archive-url=https://web.archive.org/web/20161223063154/http://accessmedicine.mhmedical.com/content.aspx?bookid=348&Sectionid=40381603 | archive-date=23 December 2016 }}</ref>

Approximately 1% of emergency department visits for children are for headache.<ref>{{cite journal | vauthors = Scagni P, Pagliero R | title = Headache in an Italian pediatric emergency department | journal = The Journal of Headache and Pain | volume = 9 | issue = 2 | pages = 83–87 | date = April 2008 | pmid = 18250964 | pmc = 3476181 | doi = 10.1007/s10194-008-0014-1 }}</ref><ref name="Kan">{{cite journal | vauthors = Kan L, Nagelberg J, Maytal J | title = Headaches in a pediatric emergency department: etiology, imaging, and treatment | journal = Headache | volume = 40 | issue = 1 | pages = 25–29 | date = January 2000 | pmid = 10759899 | doi = 10.1046/j.1526-4610.2000.00004.x | s2cid = 39115552 }}</ref> Most of these headaches are not dangerous. The most common type of headache seen in pediatric emergency rooms is headache caused by a cold (28.5%). Other headaches diagnosed in the emergency department include post-traumatic headache (20%), headache related to a problem with a [[ventriculoperitoneal shunt]] (a device put into the brain to remove excess [[Cerebrospinal fluid|CSF]] and reduce pressure in the brain) (11.5%) and migraine (8.5%).<ref name="Kan" /><ref>{{cite journal | vauthors = Burton LJ, Quinn B, Pratt-Cheney JL, Pourani M | title = Headache etiology in a pediatric emergency department | journal = Pediatric Emergency Care | volume = 13 | issue = 1 | pages = 1–4 | date = February 1997 | pmid = 9061724 | doi = 10.1097/00006565-199702000-00001 | s2cid = 33965477 }}</ref> The most common serious headaches found in children include brain bleeds ([[subdural hematoma]], [[epidural hematoma]]), [[brain abscess]]es, meningitis and [[ventriculoperitoneal shunt]] malfunction. Only 4–6.9% of kids with a headache have a serious cause.<ref name="Schultz" />

Just as in adults, most headaches are benign, but when head pain is accompanied with other symptoms such as [[speech problems]], [[muscle weakness]], and [[loss of vision]], a more serious underlying cause may exist: [[hydrocephalus]], [[meningitis]], [[encephalitis]], [[abscess]], [[hemorrhage]], [[tumor]], [[blood clot]]s, or [[head trauma]]. In these cases, the headache evaluation may include CT scan or MRI in order to look for possible structural disorders of the [[central nervous system]].<ref>{{cite web |url=http://www.webmd.com/migraines-headaches/guide/your-childs-headache |title=What Causes Headaches in Children and Adolescents? |website=[[WebMD]] |access-date=30 June 2010 |url-status=live |archive-url=https://web.archive.org/web/20130507025935/http://www.webmd.com/migraines-headaches/guide/your-childs-headache |archive-date=7 May 2013 }}</ref> If a child with a recurrent headache has a normal physical exam, neuroimaging is not recommended. Guidelines state children with abnormal neurologic exams, confusion, seizures and recent onset of worst headache of life, change in headache type or anything suggesting neurologic problems should receive neuroimaging.<ref name="Schultz" />

When children complain of headaches, many parents are concerned about a [[brain tumor]]. Generally, headaches caused by brain masses are incapacitating and accompanied by vomiting.<ref name="Schultz" /> One study found characteristics associated with brain tumor in children are: headache for greater than 6 months, headache related to sleep, vomiting, confusion, no visual symptoms, no family history of migraine and abnormal [[neurologic exam]].<ref name="pmid11483785">{{cite journal | vauthors = Medina LS, Kuntz KM, Pomeroy S | title = Children with headache suspected of having a brain tumor: a cost-effectiveness analysis of diagnostic strategies | journal = Pediatrics | volume = 108 | issue = 2 | pages = 255–263 | date = August 2001 | pmid = 11483785 | doi = 10.1542/peds.108.2.255 }}</ref>

Some measures can help prevent headaches in children. Drinking plenty of water throughout the day, avoiding caffeine, getting enough and regular sleep, eating balanced meals at the proper times, and reducing stress and excess of activities may prevent headaches.<ref>{{cite web | author = American Headache Society Committee on Headache Education. |url= http://www.achenet.com/education/patients/headachesinchildren.asp |title=Headaches in Children |publisher= American Headache Society |archive-url=https://web.archive.org/web/20080516223426/http://www.achenet.com/education/patients/headachesinchildren.asp|archive-date=16 May 2008|access-date=30 June 2010}}</ref> Treatments for children are similar to those for adults, however certain medications such as narcotics should not be given to children.<ref name="Schultz" />

Children who have headaches will not necessarily have headaches as adults. In one study of 100 children with headache, eight years later 44% of those with tension headache and 28% of those with migraines were headache free.<ref name="pmid9793697">{{cite journal | vauthors = Guidetti V, Galli F, Fabrizi P, Giannantoni AS, Napoli L, Bruni O, Trillo S | title = Headache and psychiatric comorbidity: clinical aspects and outcome in an 8-year follow-up study | journal = Cephalalgia | volume = 18 | issue = 7 | pages = 455–462 | date = September 1998 | pmid = 9793697 | doi = 10.1046/j.1468-2982.1998.1807455.x }}</ref> In another study of people with chronic daily headache, 75% did not have chronic daily headaches two years later, and 88% did not have chronic daily headaches eight years later.<ref name="pmid19605771">{{cite journal | vauthors = Wang SJ, Fuh JL, Lu SR | title = Chronic daily headache in adolescents: an 8-year follow-up study | journal = Neurology | volume = 73 | issue = 6 | pages = 416–422 | date = August 2009 | pmid = 19605771 | doi = 10.1212/WNL.0b013e3181ae2377 | s2cid = 32419124 }}</ref>

=== Cardiac Cephalgia in Heart Attack ===
Cardiac cephalgia<ref>{{Cite journal |last1=Torres-Yaghi |first1=Yasar |last2=Salerian |first2=Justin |last3=Dougherty |first3=Carrie |date=April 2015 |title=Cardiac cephalgia |journal=Current Pain and Headache Reports |volume=19 |issue=4 |page=14 |doi=10.1007/s11916-015-0481-4 |issn=1534-3081 |pmid=25819974}}</ref> is a rare type of headache occurring during myocardial infarction, characterized by sudden, severe head pain that typically develops during or immediately following a heart attack. The pain is usually located in the occipital or frontal regions and can be accompanied by other cardiac symptoms like chest pain, shortness of breath, or radiating arm pain. This specific headache type is considered a potential warning sign of cardiac distress and requires immediate medical attention to prevent potentially life-threatening complications.<ref>{{Cite web |last=Hashmi |first=Dr Hala Bashir |date=21 Oct 2024 |title=Cardiac Cephalgia in Heart Attack |url=https://health-learners.com/cardiac-cephalgia-in-heart-attack/ |website=Health Learners}}</ref>

==See also==
*[[Eye strain]]

== References ==
{{Reflist}}

== External links ==
{{wikibooks|Internal Medicine|Headache}}

{{Medical resources
| ICD10           = {{ICD10|G43}}, {{ICD10|G44}}, {{ICD10|R51}}
| ICD9            = {{ICD9|339}}, {{ICD9|784.0}}
| ICDO            =
| OMIM            =
| DiseasesDB      = 19825
| MedlinePlus     = 003024
| eMedicineSubj   = neuro
| eMedicineTopic  = 517
| MeshID          = D006261
| GeneReviewsNBK  =
| GeneReviewsName =
| NORD            =
| GARDNum         =
| GARDName        =
| Orphanet        =
| AO              =
| RP              =
| WO              =
| OrthoInfo       =
| NCI             =
| Scholia         =
| SNOMED CT       =
}}
{{Navboxes
|title=Articles and topics related to Headache
|state=collapsed
|list1=
{{CNS diseases of the nervous system}}
{{Headache}}
{{General symptoms and signs}}
{{Pain}}
}}
{{Authority control}}

[[Category:Headaches| ]]
[[Category:Medical mnemonics]]
[[Category:Pain]]
[[Category:Symptoms and signs]]