Novel drug delivery systems for controlled-release of opioid agonists as a long time painkillers or opioid antagonists for opium, heroin, and alcohol addiction are under development or in clinical use today. In this article, the field of "new drug delivery systems" is momentarily reviewed from the viewpoint of the marketed opioid agonists/antagonists dosage forms today.
Keywords: Controlled release; New drug delivery systems; Opium.