Patient compliance with drug therapy in schizophrenia. Economic and clinical issues.

The effectiveness of drug treatment in clinical practice is considerably lower than the efficacy shown in controlled studies. The lower effectiveness in practice presumably leads to lower cost effectiveness of drug treatment in real-life situations compared with that demonstrated by studies based on results from controlled trials. Improved cost effectiveness in routine clinical practice would be a significant advantage in the treatment of schizophrenia, one of the most costly diseases in society. The aetiology of schizophrenia is unknown, and there is no cure. The main aims of therapy with antipsychotic medication include the effective relief of symptoms without the introduction of adverse effects or serious adverse events, improved quality of life, cost effectiveness and a positive long term outcome. The older classical antipsychotic drugs do not always meet these requirements because of their well-known limitations, such as a lack of response in a subgroup of individuals with schizophrenia and intolerable adverse effects. There has long been a need for new antipsychotics that can ameliorate more symptoms and have no or few adverse effects. Some of the recently introduced antipsychotics have been shown to be more effective in certain clinical situations and to have a more favourable adverse effect profile than the classical antipsychotics. A major factor contributing to the lower effectiveness of drug treatment is noncompliance, which may be very high in schizophrenia. There are several factors influencing compliance, including drug type and formulation, patient, disease status, physician, health care system, community care and family. There have been very few studies of compliance improvement strategies in schizophrenia or, indeed, in medicine in general. Current methods are relatively complex and there are differing opinions on their effectiveness. There are several ways to increase compliance in schizophrenia--the evidence is strongest for psychoeducative methods, changing to a new drug or using a depot formulation. However, considerably more research is needed in the field of compliance strategies.