This study was conducted to determine the prevalence and profile of use of benzodiazepines in the Italian population and risk factors for use. Between November 1992 and February 1993, 62 general practitioners submitted a validated self-administered questionnaire on health status and drug use to a randomised sample of 3100 subjects ( > or = 18 years of age, stratified by sex and age), of whom 2803 responded (response, rate 90.4%). Main outcome measures were point estimate (past-week) of all the drugs taken by each individual, dosage and length of use and source of the prescription. The overall past-week prevalence of use of benzodiazepines was 8.6% (5.0% males and 11.8% females). In the elderly ( > or = 65 years) 18.8% reported current use (9.0% males and 24.7% females). Fifty-six per cent of the persons exposed to a benzodiazepine were chronic users (daily, for more than 6 months), and 70.1% in subjects > or = 65 years. The average daily dose taken was relatively low: 61% of short-term users and 51% of chronic users used less than half a defined daily dose (DDD). Female sex, older age, unemployment and retirement were independently associated with the use of benzodiazepines. Benzodiazepine use in Italy appeared to be relatively high (about 9% of subjects reported current use 57% of whom were chronic users). Women were prescribed a benzodiazepine twice as often as men and one out of four elderly women was on treatment. Although the average dosage used was rather low, the high prevalence and the elevated proportion of chronic users should encourage drug information campaigns and educational interventions to promote a more conservative use of these drugs especially in the elderly.