Dopamine may cause ectopic heartbeats, tachycardia, angina, palpitation, vasoconstriction, hypotension dyspnea, nausea, vomiting and headache. Other less frequent adverse effects include cardiac conduction abnormalities: QRS complex, bradycardia, hypertension, azotemia, anxiety, and piloerection. Ventricular arrhythmias may occur with very high doses. Gangrene of extremities has occurred when high doses of dopamine were administered for prolonged periods and in patients with occlusive vascular disease receiving low doses of dopamine, and extravasation of dopamine may result in tissue necrosis and sloughing of surrounding tissues.