Procainamide diarrhea with

Nausea, vomiting, and diarrhea in response to procainamide are common with dosages of 4 g/day or more (32). Pseudo-obstruction has been attributed to the use of a modified-release formulation of procainamide, perhaps due to its anticholinergic effects (33). 

Procainamide and quinidine cdrnmonly cauie Gl upset (nausea, vomiting, diarrhea) and hj otension. Less commonly, procainamide is associated with agranulocytosis end iupus-Uke syndrome Additional side effects of quinidine include thrombocytopenia and cinchonism. ... 

C. Other effects. Quinidine commonly causes nausea, vomiting, and diarrhea after acute ingestion and, especially with chronic doses, cinchonism (tinnitus, vertigo, deafness, or visual disturbances). Procainamide may cause gastrointestinal upset and, with chronic therapy, a lupus-like syndrome. 

Hypotension. Diarrhea. Dizziness. Liver failure. Lupus erythematosus-like syndrome. Nausea and vomiting. Heart block. Agranulocytosis. Procainamide increases risk of death in patients with non-life-threatening arrhythmias. Use with caution in patients with liver or kidney dysfunction. Tell patient not to crush or break extended-release tablets. 

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