A Depot Neuroleptic Withdrawal Study. A Controlled Study of the Clinical Effects of the Withdrawal of Depot Fluphenazine Decanoate and Depot Flupenthixol Decanoate in Chronic Schizophrenic Patients

A double-blind withdrawal trial in 41 chronic schizophrenic outpatients on neuroleptics was carried out during 6 months. Long-acting neuroleptics (fluphenazine decanoate or flupenthixol decanoate) were used in comparison with placebo to determine the value in maintenance therapy. Most patients had a rather low maintenance dose, about 12.5-25 mg fluphenazine decanoate or 20-40 mg flupenthixol decanoate every third week. Relapse was often characterized by a return of the dame symptoms as the patient had during his first schizophrenic attack. Drugs were significantly more effective than placebo in preventing relapse and readmission to hospital. 62% relapsed in the placebo groups as compared with 27% in the drug group. All patients on active substance and without relapse during the controlled study had their treatment discontinued for 24 months in an open follow-up investigation. This resulted in relapse of all patients but one, i.e. a final relapse frequency of 97%. A significant weight decrease was observed in the placebo group. The risk of withdrawal is discussed.