[Effect of tiapride on the activity of neuroleptics and other kinds of drugs in mice and rats].

Tiapride is a central dopamine receptor specific antagonist, and it has a benzamide chemical structure. This drug is very useful for the treatment of dyskinesia and such abnormal behaviors as delirium and psychomotor excitation in patients with arteriosclerosis. Most of these patients are elderly and generally suffer from other diseases. Since they are apt to be treated with several drugs for such diseases, the effect of tiapride in combination with various kinds of drugs was examined in rats and mice. Tiapride significantly potentiated the catalepsy-inducing effect of haloperidol and chlorpromazine in rats and tended to potentiate the muscle relaxing effect of diazepam at the highest dose in mice. Conversely, tiapride did not enhance or diminish the hypnotic effect of bromvalerylurea, the anticholinergic activity of trihexyphenidyl, the diuretic effect of bromvalerylurea, the anti-cholinergic activity of trihexyphenidyl, the diuretic effect of trichloromethiazide, or the anti-diabetic effect of glibenclamide. Our findings suggest that tiapride should be used with care in patients taking neuroleptics, but can be used freely in patients on other kinds of drugs.