Neuroleptic treatment of oligophrenic patients. A double-blind clinical multicentre trial of cis(Z)-clopenthixol and haloperidol.

One hundred mentally retarded patients from five Finnish institutions took part in a double-blind, double-dummy 12-week trial assessing the therapeutic effect of cis(Z)-clopenthixol and haloperidol. Assessments including CGI by psychiatrists and ward personnel as well as a 4-item target symptom scale was done at weeks 0, 4, 8, and 12. Improvement was registered by the psychiatrists in 16, 21, and 24 cis(Z)-clopenthixol patients and in 11, 6, and 7 haloperidol patients at weeks 4, 8, and 12, respectively--the difference between the two drugs being significant at weeks 8 and 12. The ratings of CGI by the personnel and the 4-item scale by the psychiatrists showed less improvements and no significant differences between the two drugs. While the overall impression of interference of patients' functioning by side-effects were in the favour of haloperidol the number of single side effects increased more with haloperidol than with cis(Z)-clopenthixol during the 12 weeks. Average doses administered at week 12 were 34 mg cis(Z)-clopenthixol and 5 mg haloperidol.