How Long Does Vivitrol Last?

How long Vivitrol (extended-release naltrexone) typically lasts between injections, what to expect near the end of the month, and planning the next dose.

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Key takeaway

Vivitrol is designed as a roughly once-monthly extended-release naltrexone injection. Coverage between doses can feel different near the end of the interval. Do not invent your own booster schedule. Call or text (800) 653-9376 for help finding naltrexone providers.

Last updated: Wed Oct 07 2026 00:00:00 GMT+0000 (Coordinated Universal Time)

Vivitrol is built for a monthly rhythm. "How long does it last" is really "how do I stay covered until the next injection."

Call 911 for emergencies. Call or text 988 for a crisis.

The intended interval

Extended-release naltrexone is scheduled about every four weeks under clinician care. Individual response and timing still need follow-up. Sibling: naltrexone / Vivitrol.

End-of-month worries

Cravings or sleep changes near the end of an interval are a reason to call the clinic, not a reason to use opioids to "check" the blockade.

Broker filter

A program that sells shots without explaining missed-dose plans or oral bridging options is incomplete.

Next step

Prescribing clinic, FindTreatment.gov, or call or text (800) 653-9376.

Additional Resources

Sources cited on this page:

Common Questions

How long does one Vivitrol shot last?

It is intended as a monthly extended-release injection. Your clinician sets the schedule and monitors response.

What if cravings return before 30 days?

Contact the prescribing clinic. Do not add opioids or alcohol to test whether the shot is still working.

Can I stretch doses to save money?

Changing the interval without clinical guidance risks a gap in blockade and relapse. Ask about oral naltrexone bridges or benefits help instead.

How long must I be opioid-free before the first shot?

Long enough to avoid precipitated withdrawal. Follow the clinic's protocol; do not guess from a forum.

Does the shot treat withdrawal?

No. Naltrexone is not a withdrawal-management medicine for people still physically dependent on opioids.