In the long-term treatment of schizophrenia, the costs to individuals, families and society are huge, particularly when relapse occurs. There are many ways of avoiding such relapses. For example, it has been shown that a practical cognitive behavioral approach can improve patient outcomes by engaging the patient in a collaborative alliance that encourages them to continue treatment. Such method has been demonstrated to improve insight and adherence and to reduce readmission rate.

In addition, it is generally accepted that antipsychotic drugs themselves are effective to prevent relapses of schizophrenia in long-term treatment. However, treatment adherence tends to be poor during long-term treatment. There are several factors affecting adherence to treatment. For example, acceptance of illness, level of support, family stability, positive therapeutic alliance, formulation/delivery may increase adherence, whereas side effects, poor symptom control, complex regimen, impaired judgment, and poor doctor-patient relationship can decrease it.

Long-lasting intramuscular forms of antipsychotic drugs guarantee the delivery of a measured quantity of drug. Although traditional depots have a bad image, some evidence suggests superiority of conventional depots over oral medication. Moreover, both patients on depots and British psychiatrists like them. A recent systematic review has demonstrated that depots are more effective than oral medication, although depots bring about more side effects.

Actually, as shown in the table, more than 50% of British psychiatrists who responded to a questionnaire believed that conventional depots have no advantages in efficacy over oral medication, and that they are less acceptable to patients. Not as many (less than 50%) of them considered depots to be old-fashioned or associated with more side effects than oral medication. Nonetheless most agreed that depots facilitate adherence, prevent relapse and could be used across a wide spectrum of patients (e.g. forensic, involuntary or chronic cases). If there was an atypical depot, 90% of British psychiatrists say that they would prescribe it.