Toxicologic studies of glycopyrrolate in combination with other drugs

Abstract These studies investigated the toxicology of combinations of glycopyrrolate (1-methyl-3-pyrrolidyl α-phenylcyclopentaneglycolate methobromide; Robinul ® ) with phenobarbital, meprobamate, tybamate, mephenoxalone, and with butaperazine. They involved mice, rats, and dogs, the po (capsule or diet) and ip routes of administration, and acute, subchronic, chronic, reproduction and teratologic experiments. Pharmacologic effects were generally those expected of high doses of an anticholinergic agent (mydriasis, cycloplegia, xerostomia, tachycardia) and of drugs that impair CNS function (sedation, ataxia, etc.). In the ratios employed in acute studies, glycopyrrolate did not influence significantly the lethality of the drugs with which it was combined. Changes in food intake, body weight gain, and/or organ weights were found with three combinations in subchronic or chronic studies. Resuts were essentially negative with regard to clinical studies, gross findings at autopsy, and histopathology. Studies concerned with reproductive performance or teratologic potential likewise yielded negative results.