Prescription of psychotropic drugs was investigated in a group of 589 inpatients, admitted to a Dutch general psychiatric (teaching) hospital. The dosages of antipsychotics, anticholinergics, antidepressants and anxiolytics/sedatives/hypnotics were converted to equivalent dosages of haloperidol, biperiden, amitriptyline and oxazepam, respectively and related to sex, age, duration of admission and diagnosis. The results were compared with those of a number of similar surveys in the literature.

Seventy percent of all patients were treated with an antipsychotic agent. The prescription of very high doses of antipsychotics was found to be relatively rare. The average (11 mg of haloperidol equivalent/day) and median (6.9 mg of haloperidol equivalent/day) dose of neuroleptic were found to be lower than described in several surveys in the last decade and comparable to those recently reported in two teaching hospitals in Boston and Bern. Yet the number of patients receiving more than the equivalent of 20 mg of haloperidol was substantial.

Anticholinergics were prescribed almost exclusively to patients receiving neuroleptic therapy. Thirtyfour percent of all patients receiving antipsychotics received concurrent anticholinergic agents. Biperiden was used in 87% of all cases. The median dose was 4 mg/day.

The average dosage of antidepressant prescribed was 110 mg of amitriptyline equivalent per day. This is higher than reported recently in a Swiss university hospital survey but lower than recommended in recent literature on treatment of depression. Possible reasons are discussed.

Anxiolytic/hypnotic agents were prescribed to 58% of all paÜtients. The average dose was 76 mg of oxazepam equivalent/day, the median dose 50 mg of oxazepam equivalent/day. There was a significant negative correlation between age and dose of oxazepam equivalents, but no significant sex difference in the dose of anxiolytics/ hypnotics.