Blood levels of flupenthixol in patients with acute and chronic schizophrenia.

Plasma levels of flupenthixol were estimated by three methods in 30 patients with acute schizophrenia and 29 patients with chronic schizophrenia. These levels were related to clinical response, anterior pituitary hormone secretion, platelet monoamine oxidase activity, the effects of the concurrent administration of anticholinergic drugs, and body weight. No clearcut relationships between plasma flupenthixol levels and any of these variables were demonstrated. The practical clinical value of the estimation of plasma flupenthixol is limited at the present time.