Benactyzine hydrochloride (1 mg/kg) does not influence the attention response. Benactyzine hydrochloride increases the duration of the exploratory-motor reaction, but slightly diminishes the salivation elicited by acetylcholine. There is no blocking effect of Benactyzine hydrochloride and promazine on the EEG-seizure activity elicited by acetylcholine, and almost no inhibitory effect on emotional reactions. Emotional reactions are blocked by high doses of imipramine and promazine, but not by Benactyzine hydrochloride. The data indicates that imipramine, promazine and Benactyzine hydrochloride influence the autonomic effects of serotonin in different ways. Promazine, and especially Benactyzine hydrochloride, inhibit and shorten the period of salivation elicited by the intra-amygdaloid injection of serotonin.