In addition to adverse cardiovascular effects of procainamide, other dose-related adverse effects include:

• CNS—mental depression, hallucinations, seizures, confusion, dizziness
• GI—anorexia, nausea, vomiting, diarrhea, bitter taste
• Hematologic—agranulocytosis, hemolytic anemia, neutropenia
• Skin—rash, urticaria
• Other—fever, lupus-like syndrome in long-term therapy, Raynaud’s phenomenon.