Drug reference
naltrexone
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Drug class
Musculoskeletal (Opioids)
Mechanism of action
Opioid competitive receptor antagonist; shows highest affinity for mu receptors; congener of oxymorphone
Common side effects
- Upper respiratory tract infection
- Insomnia
- Injection site reaction
- Decreased appetite
- Headache
- Nausea
- Anxiety
Contraindications
- Patients who are on opioid analgesics, are opioid-dependent (eg, opioid agonists [methadone], opioid partial agonists [buprenorphine]), are in acute opioid withdrawal, have positive urine test for opioids, or fail to pass naloxone challenge Hypersensitivity
Related conditions
Frequently asked questions
What drug class is naltrexone?
naltrexone belongs to: Musculoskeletal.
How does naltrexone work?
Opioid competitive receptor antagonist; shows highest affinity for mu receptors; congener of oxymorphone
What are the common side effects of naltrexone?
Upper respiratory tract infection, Insomnia, Injection site reaction, Decreased appetite, Headache, Nausea, Anxiety
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