Naltrexone

(nal-TREK-sohn)

Naltrexone is an opioid antagonist that blocks the effects of opioids and is used to treat OUD by preventing relapse after detoxification. It is also used in the treatment of alcohol use disorder.

Historical context

Naltrexone was first synthesized in the 1960s and gained FDA approval in the United States in 1984 for the treatment of opioid addiction. In 2006, an extended-release injectable form (Vivitrol®️) was approved for the treatment of both opioid and alcohol use disorders.

Medical formulations

Naltrexone is available as oral tablets and extended-release injectable forms (e.g., ReVia®️, Depade®️, Vivitrol®️).

How long does naltrexone stay in your system?

Naltrexone has a half-life of about 4 to 13 hours. It takes approximately 20 to 65 hours for the drug to be completely eliminated from the body.

Street names

Trex, Nalt, Vivi

Appearance

Naltrexone pills are typically round or oval and come in various colors, such as white or beige, depending on the formulation and dosage. They may be imprinted with the dosage and the manufacturer's logo.

Common pills

• Naltrexone 25 mg tablet: The tablet is white, round, and has "25" and the manufacturer's logo imprinted on it.
• Naltrexone 50 mg tablet: The tablet is white, round, and has "50" and the manufacturer's logo imprinted on it.
• Naltrexone 100 mg tablet: The tablet is white, round, and has "100" and the manufacturer's logo imprinted on it.