View source for Eye drop

{{Short description|Liquid applied directly to the eye}}
{{For|the television show|Eye Drops}}
{{See also|Ophthalmic drug administration}}
[[File:Eye drop.jpg|thumb|Eye drops being applied]]
[[File:Ocuheel Medication.jpg|thumb|These eye drops are packaged for single use, without preservatives]]

'''Eye drops''' or '''eyedrops''' are [[liquid drops]] applied directly to the surface of the [[Human eye|eye]] usually in small amounts such as a single drop or a few drops. Eye drops usually contain [[saline (medicine)|saline]] to match the [[salinity]] of the eye. Drops containing only saline and sometimes  a lubricant are often used as artificial [[tears]] to treat [[dry eyes]] or simple [[eye irritation]] such as itching or [[Eye redness|redness]]. Eye drops may also contain one or more medications to treat a wide variety of [[eye diseases]]. Depending on the condition being treated, they may contain [[steroids]], [[antihistamine]]s, [[sympathomimetic]]s, [[Beta blocker|beta receptor blocker]]s, [[parasympathomimetic]]s, [[parasympatholytic]]s, [[prostaglandin]]s, [[nonsteroidal anti-inflammatory drug]]s (NSAIDs), [[antibiotic]]s, [[Antifungal medication|antifungals]], or [[topical anesthetic]]s.

Eye drops have less of a risk of side effects than do oral medicines, and such risk can be minimized by occluding the [[lacrimal punctum]] (i.e. pressing on the inner corner of the eye) for a short while after instilling drops.

Prior to the development of single-use pre-loaded sterile plastic applicators, eye drops were administered using an [[eye dropper]], a glass pipette with a rubber bulb.

== Shelf life ==
Although most bottles of eye drops contain preservatives to inhibit contamination once opened, these will not prevent contamination indefinitely. Ophthalmologists recommend keeping bottles for no longer than three months after opening.<ref name="Shelf-life of Eye Drops">{{cite web|title=Shelf-life of Eye Drops|url=http://www.aao.org/eye-health/ask-ophthalmologist-q/eye-drop-shelf-life|website=American Academy of Ophthalmology|access-date=31 October 2016|date=10 March 2014}}</ref> Eye drops that contain no preservatives are usually packaged in single-use tubes.  Dispensers typically oversize the drops; the human eye can only handle about 25 microlitres.<ref>{{cite news|last1=Allen|first1=Marshall|title=Drug Companies Make Eyedrops Too Big, And You Pay For The Waste|url=https://www.npr.org/sections/health-shots/2017/10/18/558358137/drug-companies-make-eyedrops-too-big-and-you-pay-for-the-waste|access-date=20 October 2017|work=[[NPR]]|date=18 October 2017}}</ref>

== Types and uses ==
Different pharmacological classes of eye drops can be recognized by patients by their different colored tops. For instance, the tops to dilating drops are a different color than anti-allergy drops.

===Dry eyes===
Eyes drops sometimes do not have medications in them and are only lubricating and tear-replacing solutions. There is a wide variety of [[artificial tear]] eye drops that provide different surface healing strategies. One can find bicarbonate ions, [[Hypotonicity#Hypotonicity|hypotonicity]], high [[viscosity]] gels and ointments, and non-preserved types. They all act differently and therefore, one may have to try different artificial tears to find the one that works the best.<ref>{{cite web|last1=Jayden|first1=Wills|title=New breakthrough product to help put eye drops in|url=http://www.eyedrophelper.com/product/eye-drop-helper/|website=www.eyedrophelper.com|access-date=31 October 2016|date=1 July 2010|archive-date=22 June 2021|archive-url=https://web.archive.org/web/20210622111325/https://www.eyedrophelper.com/product/eye-drop-helper/|url-status=dead}}</ref>

===Steroid and antibiotic eye drops===
Steroid and antibiotic eye drops are used to treat eye [[infections]]. They also have [[prophylactic]] properties and are used to prevent infections after eye surgeries. They should be used for the entire time prescribed without interruptions. The infection may relapse if the use of the medication is stopped.<ref name="medicinenet">{{cite web|url=http://www.medicinenet.com/steroid_and_antibiotic_eye_drops/article.htm| title=Generic Name: Steroid and Antibiotic Eye Drops|access-date=2010-05-03}}</ref>

===Pink eye===
Antibiotic eye drops are prescribed when infection [[conjunctivitis]] is caused by bacteria but not when it is caused by a virus. In the case of allergic conjunctivitis, artificial tears can help dilute irritating allergens present in the tear film.<ref>{{cite web|url=http://www.allaboutvision.com/conditions/conjunctivitis.htm#treatment| title=Pink Eye (Conjunctivitis) Treatments|access-date=2010-05-03}}</ref>

===Allergies===
Some eye drops may contain [[histamine antagonists]] or [[nonsteroidal anti-inflammatory drug]] (NSAIDs), which suppress the optical mast cell responses to allergens including (but not limited to) aerosolized dust particles.

===Glaucoma===
Eye drops used in managing [[glaucoma]] help the eye's [[fluid]] to drain better and decrease the amount of fluid made by the eye which decreases eye pressure. They are classified by their active ingredient and they include: [[prostaglandin analogs]], [[beta blockers]], alpha agonists, and [[carbonic anhydrase inhibitors]]. There are also combination drugs available for those patients who require more than one type of medication.<ref>{{cite web|url=http://www.glaucoma.org/treating/glaucoma_medica.php|title=Glaucoma Medications and Their Side Effects|access-date=2010-05-03|archive-date=2014-08-22|archive-url=https://web.archive.org/web/20140822035121/http://www.glaucoma.org/treatment/medication-guide.php|url-status=dead}}</ref>

===Mydriatic eye drops===
These make the eye's [[pupil]] widen to maximum, to let an [[optometrist]] have the best view inside the [[eyeball]] behind the iris. Afterwards in sunny weather they can cause dazzling and [[photophobia]] until the effect of the [[mydriatic]] has worn off.

In some countries including [[Russia]] and [[Italy]], Tropicamide, a mydriatic eye drop, is used to some degree as an inexpensive recreational drug.<ref name="GHP">{{cite journal |last1=Bersani |first1=Francesco Saverio |last2=Corazza |first2=Ornella |last3=Simonato |first3=Pierluigi |last4=Mylokosta |first4=Anna |last5=Levari |first5=Ermelinda |last6=Lovaste |first6=Raffaele |last7=Schifano |first7=Fabrizio |title=Drops of madness? Recreational misuse of tropicamide collyrium; early warning alerts from Russia and Italy |journal=General Hospital Psychiatry |date=September 2013 |volume=35 |issue=5 |pages=571–573 |doi=10.1016/j.genhosppsych.2013.04.013 |pmid=23706777 |issn=1873-7714}}</ref> Like other anticholinergics, when taken recreationally, tropicamide acts as a deliriant. When injected intravenously, as is most often the case, the tropicamide may cause problems such as slurred speech, unconsciousness, unresponsiveness, hallucinations, kidney pain, dysphoria, hyperthermia, tremors, suicidal tendency, convulsions, psychomotor agitation, tachycardia and headache.<ref name="GHP"/>

==Injectable medication==
Syringe designed saline drops (e.g. Wallace Cameron Ultra Saline Minipod) are distributed in modern [[needle-exchange programme]]s as they can be used efficiently either by injection or ophthalmic (if the drug is potent in small doses) route of administer which is compared to intravenous use; by demonstration, the elimination of latanoprost acid from plasma is rapid (half-life 17 minutes) after either ophthalmic or intravenous administration.<ref>{{cite web|url=https://www.drugs.com/mmx/latanoprost.html|title=Latanoprost Drug Information, Professional|publisher=Drugs.com|access-date=18 September 2014}}</ref>

==Side effects==
[[File:Man taking eyedrops.jpg|thumb|right|Man applying eye drops]]
Steroid and antibiotic eye drops may cause stinging for one or two minutes when first used and if stinging continues, medical advice should be sought. Also, one should tell their doctor if vision changes occur or if they experience persistent [[sore throat]], [[fever]], easy [[bleeding]] or [[bruising]] when using drops with [[chloramphenicol]]. Also, one should be aware of symptoms of an allergic reaction, such as: [[rash]], [[itching]], [[swelling (medical)|swelling]], [[dizziness]], and trouble breathing.<ref name="medicinenet"/> Long term steroid use can cause many adverse effects including steroid-induced [[glaucoma]] and [[cataract]].<ref name="StatPearls">{{cite journal |last1=Feroze |first1=Kaberi B. |last2=Khazaeni |first2=Leila |title=Steroid Induced Glaucoma |journal=StatPearls |date=2021 |url=https://www.ncbi.nlm.nih.gov/books/NBK430903/ |publisher=StatPearls Publishing}}</ref>

Prostaglandin analogs may cause changes in [[iris (anatomy)|iris]] color and [[eyelid]] skin, growth of [[eyelashes]], stinging, [[blurred vision]], eye redness, itching, and burning. Beta blockers' side effects include [[low blood pressure]], reduced [[pulse rate]], [[fatigue (medical)|fatigue]], shortness of breath, and in rare occasions, reduced [[libido]] and [[Depression (mood)|depression]]. Alpha agonists can cause burning or stinging, fatigue, [[headache]], [[drowsiness]], [[dry mouth]] and [[Human nose|nose]], and also they have a higher likelihood of allergic reaction. Carbonic anhydrase inhibitors may cause stinging, burning, and eye discomfort.<ref>{{cite web|url=http://www.glaucoma.org/treating/glaucoma_medica.php|title=Side Effects|access-date=2010-05-03|archive-date=2014-08-22|archive-url=https://web.archive.org/web/20140822035121/http://www.glaucoma.org/treatment/medication-guide.php|url-status=dead}}</ref>

Lubricant eye drops may cause some side effects and one should consult a doctor if pain in the eye or changes in vision occur.  Furthermore, when redness occurs but lasts more than 3 days, one should immediately consult a doctor.{{cn|date=October 2016}}

==See also==
{{col div|colwidth=40em}}
* [[Artificial tears]]
* [[Carboxymethyl cellulose]]
* [[Mydriasis]]
* [[Refractive error]]
* [[Tetrahydrozoline hydrochloride]]
* [[Visine]]
{{colend}}

==References==
{{Reflist}}

== External links ==
* {{Wiktionary inline}}
* {{Commonscat inline|Eye drops}}

{{Dosage forms|state=expanded}}
{{Authority control}}

{{DEFAULTSORT:Eye Drop}}
[[Category:Dosage forms]]
[[Category:Drug delivery devices]]
[[Category:Ophthalmology drugs]]
[[Category:Ophthalmic drug administration]]