The present disclosure provides methods and compositions for reducing the addictive liability of
opioid analgesics in a subject, for example, by co-administering to the subject the
opioid and a
serotonin receptor type 2 (5HT2)
agonist or a
serotonin (5HT) releasing agent. The disclosed methods include methods for preventing
opioid abuse, methods for reducing the rewarding effect of an opioid, methods for reducing the addictive liability of an opioid, methods for eliminating or substantially reducing the tendency for a subject to develop physical dependence, tolerance, and / or withdrawal symptoms with respect to an opioid, and methods for eliminating or substantially reducing the tendency for a subject to use opioids in ways not prescribed, take opioids more often or in larger amounts than prescribed, and / or use opioids recreationally. The methods can be performed on a subject, such as a patient (e.g., a
human patient).