In our clinical trial with 20 male chronic patients on a mental hospital ward, clopenthixol appeared to have observable antipsychotic properties with relatively little toxicity. The observation that this drug was therapeutically effective in certain chronic sohizaphrenic patients where previous treatments had failed is in accordance with the findings of other clinical investigators and suggests that clopenthixol may deserve a place among the clinically used antipsychotic compounds.Abstract Teaser