Effect of chlorpromazine treatment on prolactin levels in cerebrospinal fluid and plasma of psychotic patients.

In psychotic patients, levels of prolactin in cerebrospinal fluid (CSF) and plasma were determined by radioimmunoassay before and after 2 and 4 weeks of treatment with chlorpromazine (CPZ). CPZ was given in one of three randomly selected fixed doses: 200, 400 or 600 mg per day. Before treatment, low levels of immunoreactive prolactin-like material (PRL) were found in the CSF of most patients. The concentration in CSF was about 20% of the plasma level. In CSF but not in plasma, the pre-treatment level of PRL was significantly higher in women than in men. During CPZ treatment, the PRL levels in CSF as well as in plasma were significantly elevated in both sexes after 2 as well as 4 weeks. The elevation was significantly greater in women, and was similar at the two time intervals studied. There was a significantly positive relationship between the dose of CPZ and the PRL elevation in both body fluids in both men and women. Before treatment no significant correlation between the PRL levels in CSF and plasma in either sex could be observed. During treatment, there was a significant correlation between the change in PRL levels in CSF and plasma in both men and women. CPZ treatment did not increase the levels of total protein, follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH) or oestradiol-(17-beta) in either the CSF or the plasma.