Schizophrenia and drug delivery systems.

Schizophrenia is a severe non-curable illness of the brain with serious consequences if nut properly treated and kept under control. Antipsychotic drugs have revolutionised the therapy and management of schizophrenia. However, patient compliance rates are notoriously poor due to the nature of the disease and troublesome side-effects, and are major causes of symptom recurrence. Although some new antipsychotic agents have been marketed to offer broader efficacy with much reduced side-effect profiles, the drug delivery systems for antipsychotics are still in the stage of conventional dosage forms, such as tablets, capsules and solutions, and need to be dosed at the frequency of 2-4 times daily. Doubtless, novel drug delivery systems. such as sustained and controlled release systems, will be useful for antipsychotics. They should reduce the frequency of dosing, enhance drug bioavailability and improve patient compliance. In this article, the specificity and characterisation of schizophrenia and pathophysiology, drug therapy, and the development and future prospects of neuroleptic drug delivery systems are reviewed.