The effects of ambucetamide on human myometrial and other preparations, and its antagonism to the menstrual stimulant.

A plain-muscle stimulant, provisionally named the "menstrual stimulant," may be involved in the causation of dysmenorrhoea. Since ambucetamide [alpha-dibutylamino-alpha-(p-methoxyphenyl)-acetamide] has been claimed to alleviate this condition, its effects on the responses of human myometrial preparations to the menstrual stimulant have been studied. Ambucetamide ragularly inhibited these responses,as well as those to vasopressin,and sometimes diminished the spontaneous rhythmical activity of the human myometrium. The rat and guinea-pig uterus, the guinea-pig and cat intestine preprarations, showed more complex responses and may therefore be less suitable for testing antispasmodic drugs intended for treatment of dysmenorrhoea.