Allergic reactions (skin rash, itching, hives, angioedema), nausea, pain in the epigastric region; anemia, thrombocytopenia, agranulocytosis, dryness of the oral mucosa, dizziness, accommodation paresis, mydriasis, blurred vision, vomiting, decreased potency, urinary retention, drowsiness.
With prolonged use in large doses - hepatotoxic effect, hemolytic anemia, aplastic anemia, methemoglobinemia, pancytopenia; nephrotoxicity (glucosuria, interstitial nephritis, papillary necrosis).