A 5-year follow-up study of chronic schizophrenics treated with clopenthixol decanoate.

Twenty-three chronic schizophrenic patients were followed-up over periods up to 5 years (1978-1983) while receiving treatment with depot injections of clopenthixol decanoate in doses ranging from 100 to 600 mg every 2 to 4 weeks. The highest single dose given was 1600 mg. Improvement in psychotic symptoms occurred progressively over the 5 years, with reduction in mean overall symptom score for schizophrenia from 7.43 to 0.88. Mean side-effects scores decreased over the same period from 2.0 to 0.5. After 5 years, 10 patients were still maintained on clopenthixol decanoate. Although during the first 2 months there was little improvement in 'negative' or 'loss' symptoms, improvement was similar in 'positive' and 'negative' symptoms after 5 years. Clopenthixol decanoate appeared to have a better calming effect than that encountered with flupenthixol decanoate. At higher doses, it caused drowsiness and subdued hostility and aggression.