A comparison of the clinical and psychological effects of diazepam and amylobarbitone in anxious patients.

1. Twenty-four anxious inpatients were treated with diazepam, amylobarbitone sodium and placebo in flexible dosage for 1 week. They each received all three treatments according to a fully-balanced design, using double-blind procedures. 2. The clinical and the psychological effects of the drugs were assessed by the comprehensive battery of psychiatrist's ratings, subjective and psychological tests before treatment and at the end of each week of treatment. The tests included self-rating of anxiolytic and hypnotic effects, reaction-time, card sorting, coding and cancellation tasks, arithmetic and tappin. 3. Diazepam improved significantly subjective anxiety and insomnia, while amylobarbitone improved only the self-rated quality of sleep. Occasion effects were absent on clinical measures, indicating that the patients did not respond to non-specific temporal factors. Performance on motor tasks improved over time because of the expected practice effect, but an impairment relative to placebo was detected on two motor tests after the barbiturate and on four other tests with a cognitive component after the benzodiazepine.