EFFECTS OF CERTAIN ANTIALLERGIC DRUGS ON EXPERIMENTAL CONJUNCTIVITIS IN GUINEA-PIGS

Effects of certain antiallergic drugs on experimental conjunctivitis w ere studied with guinea pigs. Chlorpheniramine, ketotifen and levocaba stine were effective in inhibiting histamine- and antigen-induced conj unctivitis in guinea pigs. By contrast, amlexanox was only effective i n inhibiting antigen-induced conjunctivitis. Topical application of an tigen released 46.5 +/- 3.8% of histamine from the conjunctiva in sens itized guinea pigs. Both levocabastine and amlexanox were effective in inhibiting conjunctival histamine release induced by antigen applicat ion. Lacrimal histamine contents were also increased after antigen cha llenge. The increase in the histamine content of tears was inhibited b y pretreatment with levocabastine and amlexanox, but no significant ef fect was observed with chlorpheniramine and ketotifen. From these find ings, it is concluded that certain antiallergic drugs, but not amlexan ox, exhibited potent inhibition on experimental conjunctivitis in guin ea pigs. In addition, it has been established that measurement of hist amine in the conjunctiva and tears as well as observation of conjuncti vitis syndromes are useful for evaluating the effectiveness of antiall ergic drugs on various kinds of allergic conjunctivitis in clinical si tuations.