Calan (Verapamil Injection) and alcohol

Ask your doctor before using verapamil together with ethanol. Verapamil may increase the blood levels and intoxicating effects of ethanol. This can cause symptoms of extreme drowsiness, confusion, and nausea. If you experience any of these side effect you should avoid activities requiring mental alertness. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

GENERALLY AVOID: Verapamil may increase the blood concentrations and intoxicating effects of ethanol. The exact mechanism of interaction is unknown but may involve verapamil inhibition of ethanol metabolism. In 10 healthy, young volunteers, verapamil (80 mg orally every 8 hours for 6 days) increased the mean peak blood concentration (Cmax) and the 12-hour area under the concentration-time curve (AUC) of ethanol (0.8 g/kg single oral dose) by 17% and 30%, respectively, compared to placebo. Verapamil AUCs were positively correlated to increased ethanol blood AUC values. Subjectively (i.e. each subject's perception of intoxication as measured on a visual analog scale), verapamil also significantly increased the area under the ethanol effect versus time curve but did not change the peak effect or time to peak effect.

MANAGEMENT: Patients treated with verapamil should be counseled to avoid alcohol consumption.