 Opioid replacement therapy (ORT), or opioid substitution therapy (OST), is the medical procedure of replacing an illegal opioid, such as heroin, with a longer acting but less euphoric opioid; methadone or buprenorphine are typically used and the drug is taken under medical supervision.Some formulations of buprenorphine incorporate the opiate antagonist naloxone during the production of the pill form to prevent people from crushing the tablets and injecting them, instead of using the sublingual (under the tongue) route of administration.In some countries, such as Switzerland, Austria, and Slovenia, patients may be treated with slow-release morphine when methadone is deemed inappropriate due to the individual's circumstances.