Naltrexone | Naltrexone – Bupropion Combination – Mechanism of Action, Psychopharmacology and Clinical Application

Posted on:February 21, 2020
Last Updated: November 10, 2023
Time to read: 10 minutes

Naltrexone hydrochloride is a competitive opioid receptor antagonist approved by the FDA to treat opiate dependence in 1984 and alcohol dependence in 1994. Naltrexone is a synthetic congener of oxymorphone and comes in oral 50 mg tablets (Revia), or an intramuscular extended-release formulation (Vivitrol) of 380 mg is administered once monthly.

Naltrexone is also available as a combination with Bupropion [Naltrexone HCl 8 mg and bupropion HCl 90 mg], known as Contrave and is indicated for weight loss.

Naltrexone has been shown to block the subjective response to opioids (e.g. heroin, morphine, and codeine) and alcohol, effectively suppressing physical dependence and cravings. Overall, naltrexone is just one component of a comprehensive treatment plan that includes behavioural therapies to induce abstinence, limit relapses, and improve quality of life. [Anton et al. 1999]