May cause liver damage w/ drugs leading to enzyme induction eg, certain hypnotics & anti-epileptics (eg, glutethimide, phenobarb, phenytoin, carbamazepine), rifampicin; potentially hepatotoxic substances & alcohol abuse. Prolonged t
½ of chloramphenicol w/ the risk of increased toxicity. May impact the lab determination of uric acid by phosphotungstic acid & of blood glucose by glucose oxidase-peroxidase. Intensified anticholinergic effects of tri- & tetracyclic antidepressants, antihistamines, antipsychotics, quinidine, amantadine, disopyramide & other anticholinergics (eg, tiotropium, ipratropium, atropine-like compd). Concomitant treatment w/ dopamine antagonists eg, metoclopramide HCl may result in diminution of the effects of both drugs on the GIT. Enhanced tachycardic effects of β-adrenergic agents. Acetaminophen: Reduced absorption rate & delayed onset of action w/ propantheline. Reduced absorption w/ cholestyramine. Increased absorption rate w/ metoclopramide.