Indications : Conjunctivitis, seasonal allergic FDA Class 1P (“Priority Review”) FDA Approved 1993 Nov DRUG CLASS : Ophthalmics, Miscellaneous BRAND NAMES : Livostin (US); Livostin ED (South-Africa); Levophta (Germany); (International brand names outside U.S. in italics) DESCRIPTION : Levocabastine HCl is a selective histamine H1-receptor antagonist for topical ophthalmic use. Each ml contains 0.54 mg levocabastine hydrochloride equivalent to 0.5 mg levocabastine; 0.15 mg benzalkonium chloride; propylene glycol; polysorbate 80; dibasic sodium phosphate, monohydrate; disodium edetate; hydroxypropyl methylcellulose; and purified water. It has a pH of 6.0 to 8.0. The chemical name for levocabastine hydrochloride is (-)-trans -1-(cis -4-Cyano-4-(p-fluorophenyl)cyclohexyl)-3-methyl-4- phenylisonipecotic acid monohydrochloride. CLINICAL PHARMACOLOGY : Levocabastine is a potent, selective histamine H1-antagonist. Antigen challenge studies performed two to four hours after initial drug instillation indicated activity was maintained for at least two and four hours. In an environmental study, levocabastine HCl instilled four times daily was shown to be significantly more effective than its vehicle in reducing ocular itching associated with seasonal allergic conjunctivitis. After instillation in the eye, levocabastine is systemically absorbed. However, the amount of systemically absorbed levocabastine after therapeutic ocular doses is low (mean plasma concentrations in the range of 1-2 ng/ml). INDICATIONS AND USAGE : Levocabastine HCl is indicated for the temporary relief of the signs and symptoms of seasonal allergic conjunctivitis. CONTRAINDICATIONS : This product is contraindicated in persons with known or suspected hypersensitivity to any of its components. It should not be used` while soft contact lenses are being worn. WARNINGS : For topical use only. Not for injection. PRECAUTIONS : Information for Patients : SHAKE WELL BEFORE USING. To prevent contaminating the dropper tip and suspension, care should be taken not to touch the eyelids or surrounding areas with the dropper tip of the bottle. Keep bottle tightly closed when not in use. Do not use if the suspension has discolored. Store at controlled room temperature. Protect from freezing. Carcinogenesis, Mutagenesis, and Impairment of Fertility : Levocabastine was not carcinogenic in male or female rats or in male mice when administered in the diet for up to 24 months. In female mice, levocabastine doses of 5,000 and 21,500 times the maximum recommended ocular human use level resulted in an increased incidence of pituitary gland adenoma and mammary gland adenocarcinoma possibly produced by increased prolactin levels. The clinical relevance of this finding is unknown with regard to the interspecies differences in prolactin physiology and the very low plasma concentrations of levocabastine following ocular administration. Mutagenic potential was not demonstrated for levocabastine when tested in Ames’ Salmonella Reversion test or in Escherichia coli , Drosophila melanogaster , a mouse Dominant Lethal Assay or in rat Micronucleus test. In reproduction studies in rats, levocabastine showed no effects on fertility at oral doses of 20 mg/kg/day (8,300 times the maximum recommended human ocular dose). Teratogenic Effects: Pregnancy Category C. Levocabastine has been shown to be teratogenic (polydactyly) in rats when given in doses 16,500 times the maximum recommended human ocular dose. Teratogenicity (polydactyly, hydrocephaly, brachygnathia), embryotoxicity, and maternal toxicity were observed in rats at 66,000 times the maximum recommended ocular human dose. There are no adequate and well-controlled studies in pregnant women. Levocabastine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Nursing Mothers : Based on determinations of levocabastine in breast milk after ophthalmic administration of the drug to one nursing woman, it was calculated that the daily dose of levocabastine in the infant was about 0.5 mcg. Pediatric Use : Safety and effectiveness in children below the age of 12 have not been established. ADVERSE REACTIONS : The most frequent complaint with the use of levocabastine HCl is that of mild, transient stinging and burning (15%) and headache (5%). Other adverse experiences which have been reported in approximately 1-3% of patients treated with Livostin include visual disturbances, dry mouth, fatigue, pharyngitis, eye pain/dryness, somnolence, red eyes, lacrimation/discharge, cough, nausea, rash/erythema, eyelid edema, and dyspnea. DOSAGE AND ADMINISTRATION : Shake Well Before Using. The usual dose is one drop instilled in affected eyes four times per day. Treatment may be continued for up to 2 weeks. HOW SUPPLIED : Livostin 0.05% 2.5 ml, 5 ml and 10 ml, is provided in white, polyethylene dropper tip squeeze bottles. Keep tightly closed when not in use. Do not use if the suspension has discolored. Store at controlled room temperature 15 to 30°C (59 to 86°F). Protect from freezing.