Promolate is an Isobutyric acid derivative with potent antitussive activity. In preclinical studies, Promolate shows low toxicity in experimental animals and an antitussive action like that of codeine, but without the side effects of the latter. Promolate displayed a dose-dependent antitussive effect in conscious guinea pigs with coughing induced by NH3 aerosol. The activity of Promolate did not diminish when it was administered orally to guinea pigs for 20 days. Promolate also displayed a dose-dependent antitussive effect in Na barbital anesthetized cats with coughing induced by stimulation of the superior laryngeal nerve. High doses of Promolate administered to rats for 125 days did not provoke side effects.