Key takeaway
Vivitrol is a monthly intramuscular naltrexone injection given by a clinician for alcohol use disorder or, after full opioid detox, opioid use disorder. It is not Narcan and not a home shot. Call or text (800) 653-9376 for help finding induction-ready providers.
Last updated: Wed Oct 07 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
The monthly shot is extended-release naltrexone. A clinician prepares and injects it. You do not mix it at home.
Call 911 for overdose. Call or text 988 for a crisis.
What the shot does
Naltrexone blocks opioid receptors. For alcohol use disorder it can reduce craving and heavy drinking when paired with counseling. For opioid use disorder it is only appropriate after opioids are fully out of the system.
Sibling explainers: naltrexone and Vivitrol, naloxone vs naltrexone.
Timing and overdose risk
Starting too soon after opioids can cause precipitated withdrawal. After a dose wears off, tolerance is lower - trying to "override" the block with large opioid amounts can be fatal. Keep naloxone available.
Broker filter
Anyone who confuses the Vivitrol shot with Narcan, Suboxone, or a detox sedative is not qualified to plan your medication care.
Next step
Call or text (800) 653-9376 to find clinicians who offer extended-release naltrexone and coordinate the opioid-free window when needed.
Additional Resources
Sources cited on this page:
- SAMHSA: Naltrexone
- FDA Vivitrol prescribing information
- SAMHSA FindTreatment.gov
- 988 Suicide & Crisis Lifeline
Common Questions
What is the Vivitrol shot?
Vivitrol is extended-release naltrexone injected into a muscle about once a month by a practitioner. It blocks opioid receptors and is used for alcohol use disorder and, after opioids are fully cleared, opioid use disorder.
How is it different from naloxone (Narcan)?
Naloxone reverses opioid overdose in an emergency. Vivitrol is a planned treatment medicine. See [naltrexone and Vivitrol](/guides/naltrexone-vivitrol/) for the longer explainer.
Can I get the shot the day after using opioids?
Usually no. Starting too soon can precipitate severe withdrawal. Clinicians typically wait at least 7 to 10 days after short-acting opioids, longer after methadone or buprenorphine.
Does Vivitrol treat alcohol withdrawal?
No. It does not treat acute alcohol withdrawal. Detox and CIWA-guided care come first when needed.
Where can I find a clinic that gives Vivitrol?
Ask your clinician, search FindTreatment.gov, or call or text (800) 653-9376 for matching help.