Insert, artificial tear

An erodible insert developed as a potential ocular drug-delivery system is marketed as a prescription drug for the lubricant properties of the polymer base. Lacrisert is a sterile ophthalmic insert used in the treatment of moderate to severe dry eye syndrome and is usually recommended for patients unable to obtain symptomatic relief with artificial tear solutions. The insert is composed of 5 mg of hydroxypropylcellulose in a rod-shaped form about 1.27 mm diameter by about 3.5 mm long. No preservative is used, since it is essentially anhydrous. The quite rigid cellulose rod is placed in the lower conjunctival sac and first imbibes water from the tears and after several hours forms a... 

The sustained release of artificial tears has been achieved by a hydroxypropylcel-lulose polymer insert [77], However, the best known application of diffusional therapy in the eye, Ocusert-Pilo, as shown in Figure 7, is a relatively simple structure with two rate-controlling membranes surrounding the drug reservoir containing... 

The device is generally comfortable and well accepted by many patients, but its use does have certain disadvantages. Some patients have problems with discomfort (foreign body sensation) or expulsion of the Lacrisert.The insert can be wetted with saline before insertion to improve comfort, but this can make even more difficult the insert s placement into the lower cul-de-sac, which requires a moderate amount of dexterity. Supplementation with artificial tears after insertion may improve comfort. The most common patient complaint is blurred vision associated with the intense release of polymer during the first 4 to 6 hours after instillation, from a thickened tear film.Adding such fluid as drops of NaCl 0.9% or artificial tear solution can reduce the tear film viscosity and minimize the visual complaints. As the insert dissolves it releases debris that can blur vision and cause irritation. Most patients with mild signs and symptoms of dry eye do not experience improvement with use of the insert, as compared with the use of conventional tear solutions. Because some tear secretion is necessary to dissolve the Lacrisert, KCS patients with low basal tear secretion may not benefit from or tolerate its use. 

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