Tachycardia, hypotension, hypertension, conduction block, cardiac arrest causing syncope, vomiting, delayed gastric emptying, decreased bowel movements, urinary retention, oliguria or anuria, fluid retention, water intoxication, hyponatremia, metabolic acidosis, hyperglycemia, elevated muscle creatine phosphokinase, and other side effects. Whether an overdose has occurred can be confirmed by monitoring the drug’s blood levels and determining the degree of overdose. There is no specific antidote for drug overdose, symptomatic treatment is required and supportive therapy is given.