Ethanol and oral diazepam absorption.

Despite widespread use and abuse of ethanol and diazepam in combination, little is known about the effects of ethanol on diazepam absorption. We administered diazepam (0.07 mg per kilogram of body weight) with water and with 30 ml of 50 per cent ethanol to seven normal volunteers. Plasma diazepam levels were significantly higher at 60 minutes (P less than 0.05), 90 minutes (P less than 0.01), 120 minutes (P less than 0.01), and 240 minutes (P less than 0.01) when diazepam was administered with ethanol than with water alone. Since maximum mean plasma diazepam levels after combined ingestion with ethanol were nearly twice as high than after diazepam and water (373 ng per milliliter versus 197 ng per mililiter at 60 minutes) we conclude that ethanol enhanced diazepam absorption.