The Medical Letter on Drugs and Therapeutics
A Morphine/Naltrexone Combination (Embeda) for Pain
Subscribers: Log in to read full article.  Not a subscriber?  Subscribe or purchase article.

The FDA has approved an agonist/antagonist combination of morphine and naltrexone (Embeda – King) for treatment of chronic moderate to severe pain requiring around-the-clock analgesia for an extended period of time. The addition of naltrexone is intended to prevent abuse of morphine.

MECHANISM OF ACTION — Naltrexone (ReVia, and others) is an opioid receptor antagonist known to block the pharmacologic effects of morphine. The new combination is formulated as capsules of extended-release morphine pellets that contain a sequestered core of naltrexone. If the pellets are swallowed, the morphine is gradually released and absorbed, while the naltrexone core should pass through the gut intact. If the pellets are crushed, chewed or dissolved in an attempt to release all of the morphine at once, naltrexone would also be released and should block morphine-induced euphoria.


The Medical Letter is a subscriber-funded nonprofit organization that publishes critical appraisals of new prescription drugs and comparative reviews of drugs for common diseases.

Would you like to read the rest of this article?  Gain access below.

Subscriptions to The Medical Letter on Drugs and Therapeutics include:
  • Print version published and mailed biweekly (26 issues/year)
  • Unlimited online access to current and past issues (1988 - present)
  • Mobile App for iOS, Android, and Kindle Fire
  • FREE online per issue CME/CE
Purchase this article:
Title: A Morphine Naltrexone Combination (Embeda) for Pain
Article code: 1334b
 Electronic, downloadable article - $45
Gain access through your organization
Ask your librarian to consider an Institutional Subscription to The Medical Letter.
Recommend to your librarian