Opioid Antagonists


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Expiration Date

31 Dec 2023

Last Reviewed

1 Jan 2021

Estimated Time To Finish

75 Minutes

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Activity Description

Opioid receptor antagonists block one or more of the opioid receptors in the central or peripheral nervous system. Opioid receptors are specific transmembrane neurotransmitter receptors that couple G-proteins, which upon stimulation by endogenous or exogenous opioids, leading to the intracellular process of signal transduction. The two most commonly used centrally acting opioid receptor antagonists are naloxone and naltrexone. Naloxone comes in intravenous, intramuscular, and intranasal formulations and is FDA-approved for the use in an opioid overdose and the reversal of respiratory depression associated with opioid use. Naltrexone is available in both oral and long-acting injectable formulations and is FDA-approved to treat opioid and/or alcohol maintenance treatment. The most commonly used peripheral opioid receptor antagonist is methylnaltrexone, which is a potent competitive antagonist acting at the digestive tract and is also FDA-approved for the treatment of opioid-induced constipation. This activity outlines the indications, mechanism of action, methods of administration, important adverse effects, contraindications, monitoring, and toxicity of opioid antagonists, so providers can direct patient therapy to optimal outcomes to combat opioid overdose, misuse, or adverse effects.

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Target Audience

This activity has been designed to meet the educational needs of physicians.

Learning Objectives

At the conclusion of this activity, the learner will be better able to:

  • Identify the mechanism of action of various opioid antagonist medications.
  • Summarize the different indications for the various opioid antagonist agents.
  • Review the adverse event profile of opioid antagonists.
  • Outline the importance of collaboration and communication among interprofessional team members to improve outcomes and treatment efficacy for patients who might benefit from therapy with opioid antagonists, especially in light of the ongoing opioid crisis.

Author(s) / Contributors Disclosure of Conflicts of Interest

Each author, editor, faculty and planning committee member have completed a disclosure form indicating that neither they nor their spouse/partner has a financial interest/arrangement or affiliation that could be perceived as a real or apparent conflict of interest related to the content of this activity.

COMMERCIAL SUPPORT: This activity has received NO commercial support.

Continuing Education Accreditation Information

This activity has been planned and implemented in accordance with the accreditation requirements and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint providership of the Quillen College of Medicine, East Tennessee State University, and StatPearls, LLC. The Quillen College of Medicine, East Tennessee State University is accredited by the ACCME to provide continuing medical education for physicians.

Quillen College of Medicine, East Tennessee State University designates this activity for a maximum of 1.25 AMA PRA Category 1 CreditsTM. Physicians should only claim credit commensurate with the extent of their participation in the activity.

This activity is reported to the following Maintenance of Certification (MOC) boards:
American Board of Internal Medicine
  • Critical Care Medicine
  • Internal Medicine
American Board of Pathology
  • Chemical Pathology
American Board of Pediatrics
  • Medical Toxicology

Cancellation Policy: Cancellations must be received in writing and a money-back guarantee is provided if not completely satisfied.

  • StatPearls and ETSU reserve the right to cancel any course due to unforeseen circumstances. StatPearls and ETSU will not be responsible for other expenses incurred by the participant in the unlikely event that the program is canceled.

Equal Opportunity

  • StatPearls and ETSU are Equal Opportunity / Affirmative Action / Equal Access Institutions. 

Medium or Media Used:

  • Computer Requirements:  Internet Access
  • E-mail Address

Instructions for Credit

  1. Register for the activity and create a StatPearls login.     
  2. Review the required accreditation information:  Target audience, learning objectives, and disclosure information.
  3. Complete the entire self-study activity.
  4. Complete the post-test assessments.
  5. Successfully pass the post-test with a minimum score of 100%.
  6. Complete the evaluation survey. 
  7. Obtain a certificate.

StatPearls and ETSU adhere to ACCME Standards regarding commercial support of continuing medical education. It is the policy of StatPearls and ETSU that the faculty and planning committee disclose real or apparent conflicts of interest relating to the topics of this educational activity, that relevant conflict(s) of interest are resolved, and also that authors and editors will disclose any unlabeled/unapproved use of drug(s) or device(s) during their presentation. Detailed disclosure will be made prior to starting the activity.

The information provided at this CME/CE activity is for continuing education purposes only and is not meant to substitute for the independent medical/clinical judgment of a healthcare provider relative to diagnostic and treatment options of a specific patient’s medical condition.

  • If you need help with the system or have a question about content, please contact support@statpearls.com
  • If you have a question about the ETSU CME providership, please contact wolfes1@etsu.edu.


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