Diazepam loading in alcohol withdrawal: clinical pharmacokinetics.

The pharmacokinetics of diazepam and its major active metabolite, desmethyl-diazepam, following a loading dose of diazepam (fixed oral doses of 20 mg) were studied in 16 patients on alcohol withdrawal. No toxic drug levels were measured irrespective of the amount of diazepam needed on the loading (83 +/- 27 mg on average). The mean elimination half-life of diazepam fell within the range observed in healthy persons after the ingestion of therapeutic doses (5), or it was only moderately prolonged (t1/2 49.7 h). The ageing process was associated with a slightly prolonged half-life of diazepam. Standard liver function tests could not predict the length of the elimination half-life of diazepam. Active drug concentrations remained high during the first 48 h of treatment, followed by a steady decline. On the basis of this study, it seems that diazepam can be safely and effectively used in loading doses in the treatment of alcohol withdrawal.