Detrimental haemodynamic effects of cyclizine in heart failure.

The haemodynamic effects of intravenous cyclizine, an antiemetic that is widely given with opioids in left ventricular failure and myocardial infarction, were studied in 11 patients with severe heart failure. Cyclizine significantly increased systemic and pulmonary arterial pressures, and right and left ventricular filling pressures, and negated the venodilatory effects of diamorphine. The use of cyclizine in patients with heart failure should, therefore, be avoided.