Cardiovascular: Facial flushing, headache, sweating, palpitations, chest pain, hypotension. Respiratory: Shortness of breath/dyspnea, chest pressure, hyperventilation, head pressure. Central Nervous System: Lightheadedness, dizziness, tingling in arms, numbness, apprehension, blurred vision, burning sensation, heaviness in arms, neck and back pain. Gastrointestinal: Nausea, metallic taste, tightness in throat, pressure in groin. In post-market clinical experience with Adenosine, cases of prolonged asystole, ventricular tachycardia, ventricular fibrillation, transient increase in blood pressure, bradycardia, hypotension, atrial fibrillation and bronchospasm, in association with Adenosine use, have been reported.