Extended release drug delivery strategies in psychiatry: theory to practice.

OBJECTIVE: An overview of the emerging field of long-term delivery strategies for improved convenience and adherence with psychiatric medications is provided. This review is motivated by the hypothesis that adherence to treatment is an important determinant of clinical outcomes in a wide range of settings and is particularly important in psychiatry practice where patients require treatment for months or years and premature discontinuation can have serious consequences for patient health and quality of life.
DESIGN: The author reviews the relevant literature and highlights several approaches to providing improved access to continuous medication through new and innovative delivery strategies ranging from days to annual intervals.Benefits and Disadvantages: Several solutions to the problem of discontinuous access to pharmacotherapy are being developed in the form of new, long-acting drug-delivery systems, which gradually release medication over a period of several days or weeks with a single application. Long-acting formulations of psychiatric medications offer a number of potential benefits in comparison with conventional immediate-release agents, including improved safety and effectiveness. Potential limitations to using long-acting formulations may include pain and discomfort at the injection site, perceived inconvenience of a new treatment method, preference for oral medications, and length of time to titrate down to the lowest effective dose.
CONCLUSIONS: The introduction of new, long-acting drug formulations could provide significant improvements in clinical outcomes and patient satisfaction for many patients, including those with affective disorders, schizophrenia, and alcohol dependence. Switching from oral administration to these new agents requires careful monitoring to reach the optimal dose, and patient concerns regarding the use of new delivery methods must be addressed. Long-acting formulations are not intended to be a sole form of treatment, and the use of psychotherapy as an adjunct form of treatment is still required. Controlled clinical trials of these new formulations have only recently been completed, offering clinicians a new option in their treatment regimens; however, as technologies improve, several new formulations are likely to enter clinical trials during the next few years. Psychiatrists will need to become acquainted with these technologies and educate their patients about them so they may work together to determine the most effective treatment option.