The anticholinergic side effects of disopyramide and controlled-release disopyramide

Until now, the potential antiarrhythmic benefits of disopyramide have been restricted by anticholinergic side effects. These side effects have included xerostomia (dry mouth, nose or eyes), abdominal discomfort, nausea, constipation and, most importantly, urinary hesitancy and retention. A sustained-release form of pyridostigmine, an acetyl-cholinesterase inhibitor, has been shown to a) prevent the anticholinergic side effects of disopyramide when used prophylactically and b) to eliminate or attenuate these symptoms if they are already present. Pyridostigmine has no measurable effect on disopyramide's antiarrhythmic properties. This represents a beneficial new drug interaction which will improve tolerance of disopyramide and increase patient compliance with disopyramide-containing regimens.