Drug Release

Abstract

Drug release refers to the process by which drug molecules are transferred from their initial position in a drug delivery system to the outer surface, and in turn, as solutes, into the release medium. “Drug release” is often used interchangeably with drug dissolution, although drug dissolution represents only one step in the more complex process of drug release. Dissolution from drug delivery systems occurs only when the drug is initially in the solid state, as in a tablet or ointment, or when it deliberately precipitates at the site of administration, as in subcutaneous or intramuscular depot formulations, such as insulin glargine. Drug release is a prerequisite of drug absorption. Drug molecules should be dissolved at the absorption site for their absorption to occur.