Artificial tears
Artificial tears are lubricant eye drops used to treat the dryness and irritation associated with deficient tear production in keratoconjunctivitis sicca (dry eyes).[1] They are also used to moisten contact lenses and in eye examinations.
Artificial tears are available over-the-counter. Artificial tears are supplemented with other treatments in moderate to severe forms of dry eyes.
Contents
Chemistry
Preparations contain carboxymethyl cellulose,[1][2] hydroxypropyl methylcellulose[2] (a.k.a. HPMC or hypromellose), and hydroxypropyl cellulose[1]. They contain water, salts and polymers but lack the proteins found in natural tears. Patients who use them more frequently than once every three hours[1] should choose a brand without preservatives[1] or one with special non-irritating preservatives.
Effects
Application of artificial tears every few hours[3] can provide temporary relief from the symptoms of dry eyes. Hydroxypropyl cellulose stabilizes and thickens the precorneal tear film, and prolongs the tear film breakup time.[1]
Usage
Artificial tears usually are the first line of treatment for dry eyes.[2] While mild cases require application of lubricant drops four times a day, severe cases require more aggressive treatment, such as ten to twelve times a day.[1] Thicker artificial tears can be used in severe cases, although these may temporarily blur vision.[1]
An artificial tear insert such as Lacrisert, a formulation of hydroxypropyl cellulose manufactured by Aton Pharma, can also be used every morning.[1] Lacrisert does not contain any preservatives.[4] It helps to retain tears by maintaining the tear film on the surface of the eye longer.[4][5]
Precautions
Drops for red eyes can make the eyes even drier.[2] If wearing contact lenses, rewetting or lubricating drops specifically for contact lenses should be used.[2] Other types of drops may contain ingredients that damage the lens.[2]
Adverse effects, interactions and contraindications
Possible adverse effects of carboxymethyl cellulose and other similar lubricants include eye pain, irritation, continued redness, or vision changes.[1] Use should be discontinued if any of them occur.[1] Those of hydroxypropyl cellulose include hyperaemia, photophobia, stickiness of eyelashes, discomfort, and irritation.[1] Long term use of preservatives present in some artificial tears may harm the eye.[citation needed]
Artificial tears have no reported interactions.[1] A documented contraindication of artificial tears is hypersensitivity.[1]
Veterinary uses
Artificial tears are a part of the topical therapy for keratoconjunctivitis sicca for animals such as dogs, cats and horses.[6]
External links
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 "Keratoconjunctivitis, Sicca". eMedicine. WebMD, Inc. 2006-04-21. Retrieved 2006-11-12.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Lua error in package.lua at line 80: module 'Module:Citation/CS1/Suggestions' not found.
- ↑ "Keratoconjunctivitis Sicca". The Merck Manual, Home Edition. Merck & Co., Inc. 2003-02-01. Retrieved 2006-11-12.
- ↑ 4.0 4.1 Lacrisert [prescribing information]. Lawrenceville, NJ: Aton Pharma, Inc; 2007.
- ↑ Katz JI, Kaufman HE, Breslin C, Katz IM. Slow-release artificial tears and the treatment of keratitis sicca. Ophthalmology. 1978;85(8):787-793.
- ↑ "Keratoconjunctivitis, Sicca". The Merck Veterinary Manual. Merck & Co., Inc. Retrieved 2006-11-18.