Pipamperone (Dipiperon, R3345) in troublesome mental retardates: a double-blind placebo controlled cross-over study with long-term follow-up.

A 6-week double-blind cross-over study comparing pipamperone with placebo was conducted in 20 female mental retardates with behavioural disorders. The ages of the patients ranged between 22 and 42 years. After a 2-week washout period, patients were randomly allocated to either pipamperone or placebo treatment. The initial dosage of pipamperone was 40 mg b.i.d., which was gradually increased to 80 mg b.i.d. within 5 days. Patients were assessed using a ten-item rating scale before and after each week of treatment. For six of the ten items, patients showed a better response during the pipamperone than during the placebo period. When pre-trial scores were compared with those at the end of the trial, seven items had significantly improved with pipamperone. The nursing staff considered the patients more alert and amenable during pipamperone treatment.