Drug Formulation Advances in Extended-Release Medications for Pain Control.

Prescription opioid abusers frequently tamper with opioid tablets in order to either accelerate the delivery of the euphoria-inducing agent or to alter the route of delivery, such that it may be delivered intranasally or intravenously. As one strategy to combat the opioid epidemic in the USA, drug manufacturers have begun to explore formulations which resist such tampering by abusers. Techniques to prevent tampering consist of physical barriers to crushing, chewing, and drug extraction, or aversive or antagonistic agents, incorporated within the formulation itself. Recent years have seen the development of numerous extended-release opioid agents, which are described in this review. This article provides a comprehensive summary of the pharmacology, benefits, risks, and processes behind the development of currently available extended-release opioid drugs, as well as a glimpse into promising future formulations.