Failure of terfenadine as an antipruritic agent in atopic dogs: results of a double-blinded, placebo-controlled study.

Terfenadine (5 mg/kg body weight, q12h) and placebo (0.5 grain/dog q12h) were both administered orally as individual agents to 18 dogs with atopy in a double-blinded study. No dog improved. Hyperactivity, polyphagia, lethargy, anorexia, increased pruritus, or ocular discharge were seen in three dogs treated with terfenadine. Under the conditions of the study, terfenadine was not a useful antipruritic agent for the atopic dog.