Ceruletide resembles antipsychotics in rats and schizophrenic patients. Preliminary report.

Peptides related to the C-terminal part of cholecystokinin, including ceruletide, were found to be active in a number of behavioral test procedures in rats, predicting antipsychotic action. In a subsequent clinical trial ceruletide was administered intramuscularly in a dose of 40 micrograms twice for 2 consecutive weeks to 6 neuroleptic-treated schizophrenic patients following a single-blind design. In 3 patients, a pronounced long-lasting antipsychotic effect was observed, while in the other 3 the response was less marked. It is suggested that ceruletide may be a potential antipsychotic peptide.