Drug Delivery: Controlled Release

Over the past decades, the treatment of illness has been accomplished by administering drugs to the human body via various pharmaceutical dosage forms, like tablets. These traditional pharmaceutical products are still commonly seen today in the prescription and over-the-counter drug marketplace. To achieve and maintain the drug concentration in the body within the therapeutic range required for a medication, it is often necessary to take this type of drug delivery system several times a day. This yields an undesirable ‘‘seesaw’’ drug level in the body (Fig. 1). A number of advancements have been made recently in the development of new techniques for drug delivery. These techniques are capable of regulating the rate of drug delivery, sustaining the duration of therapeutic action, and/or targeting the delivery of drug to a specific tissue. These advancements have already led to the development of several novel drug delivery systems that could provide one or more of the following benefits: