Vivitrol: The Monthly Naltrexone Shot for Alcohol and Opioid Use Disorder

Vivitrol at a glance

Vivitrol pages on this site

One shot releases naltrexone over about a month

Vivitrol's naltrexone sits inside tiny beads made of a polymer (polylactide-co-glycolide) that slowly break down in the muscle.¹ Naltrexone binds to the body's opioid receptors, mainly the mu receptor, and blocks the effects of opioids such as heroin or opioid pain medicines. How it lowers drinking is not fully understood; animal research points to the body's own opioid system.¹

Source: Vivitrol label, sections 5.1 and 12.3.¹ How quickly drinking changed after the first shot in its trial is on how long naltrexone takes to work.

Over 28 days, one shot delivers 3 to 4 times the total naltrexone of a daily 50 mg tablet, and its half-life is 5 to 10 days, set by how fast the polymer erodes.¹

Vivitrol does not make you sick if you drink: it causes no disulfiram-like (Antabuse-like) reaction. In studies it was not associated with tolerance or dependence.¹

Approved for alcohol after you stop drinking, and for opioids after detox

Alcohol dependence. The approval covers people "able to abstain from alcohol in an outpatient setting prior to initiation of treatment," and you should not be actively drinking at the first shot.¹ Vivitrol does not ease alcohol withdrawal, so anyone physically dependent on alcohol needs a withdrawal plan with a clinician first.¹ The broader picture on alcohol medicines is on our naltrexone for alcohol use disorder page.

Opioid dependence. Vivitrol is approved to prevent relapse after opioid detox.¹ It is not a detox medicine, and it can set off sudden withdrawal if opioids are still in your body (see below). For opioid use disorder, SAMHSA's treatment guide says daily naltrexone tablets "have not been shown to be more effective than treatment without medication or placebo because of poor patient adherence."¹³

For both uses, the shot is meant to go with counseling or other support. It is not known whether it is safe and effective in children.¹

Opioid trials: fewer relapses while on the shot

Three randomized trials tested Vivitrol in opioid use disorder.

• Placebo-controlled trial, 250 adults after detox, 24 weeks (Russia). People on Vivitrol had confirmed opioid-free results in a median 90% of weeks, against 35% on placebo. They stayed in treatment longer (median more than 168 days vs 96), and 1 person on Vivitrol returned to physical opioid dependence, against 17 on placebo. No one on Vivitrol overdosed or died. Alkermes funded the trial.¹⁴ This is the same trial that gives the label's 36% vs 23% figure.¹
• US criminal justice trial, 308 adults, 24 weeks of treatment. Compared with usual care (brief counseling and referrals), 43% on Vivitrol relapsed vs 64%, and relapse came later (median 10.5 vs 5.0 weeks). About a year after the shots ended, the share of opioid-negative urine tests was the same in both groups (46%). Over 78 weeks there were no overdoses in the Vivitrol group and 7 in the usual-care group.¹⁵
• Head to head with Suboxone, 570 adults (X:BOT). Covered in the next section.¹⁶

Vivitrol is harder to start than Suboxone, and similar once started

Suboxone is buprenorphine plus naloxone; buprenorphine partly switches opioid receptors on and is a Schedule III controlled substance, while naltrexone blocks the receptors and is not controlled.^11,16,17 In the X:BOT trial of 570 adults, 72% of those assigned Vivitrol got a first shot against 94% who started Suboxone, and among people who did start, relapse rates were similar.¹⁶ Switching from buprenorphine or methadone to Vivitrol carries a withdrawal risk for as long as 2 weeks.¹ Starting rules, switching and overdose records are compared on naltrexone vs Suboxone.

Alcohol trials: a modest effect, clearest in people who had already stopped

The pivotal alcohol trial gave at least one shot to 624 alcohol-dependent adults. Over 24 weeks, 380 mg lowered the rate of heavy drinking days by 25% against placebo.¹⁸ When the label breaks that trial down, the gains in drinking days, heavy drinking days and staying abstinent came from the 53 people (8%) who had not drunk at all in the week before the first shot. "The same treatment effects were not evident" in the 92% who were still drinking.¹ The shot and the tablet trials are compared side by side on does naltrexone work?

Reviews that pooled trials found smaller, mixed effects:

• A 2014 meta-analysis found no effect on returning to any drinking or to heavy drinking, but a 4.6-percentage-point drop in heavy drinking days (95% CI, 0.56-8.5).¹⁹
• A 2023 meta-analysis found about 5 fewer drinking days a month (95% CI, 0.5-9.5). The federal review behind it rated this evidence low-strength.^2,20

No trial has shown the shot cuts drinking more than naltrexone tablets, though people stay on the shot longer.^21,22 The head-to-head evidence is on naltrexone vs Vivitrol.

Before the first shot, be opioid-free and honest about it

Because Vivitrol blocks opioids for weeks, starting it with opioids still in your body can bring on sudden, severe withdrawal. The label recommends at least 7 to 10 opioid-free days after short-acting opioids, and warns that people coming off buprenorphine or methadone can be at risk for as long as 2 weeks. The patient Medication Guide puts it as 7 to 14 days. This includes tramadol and cough, cold or diarrhea medicines that contain an opioid.¹

Clinics check in two ways¹:

• A urine drug test. A positive opioid result rules out the shot that day.
• A naloxone challenge test. A small injection of naloxone; if it causes withdrawal symptoms, you don't start yet, and the test can be repeated later.

Neither check is fully reliable. A few people have gone into withdrawal after a negative urine test or a passed challenge, usually when coming off buprenorphine.¹ This withdrawal "can be severe enough to require hospitalization." It has also happened in people treated for alcohol whose prescriber didn't know they used opioids.¹ Tell your prescriber about every opioid you've taken, prescribed or not.

Symptoms of opioid withdrawal include anxiety, sweating, yawning, a runny nose, goose bumps, muscle aches, vomiting, diarrhea and stomach cramps. Don't get the shot if you have them. If a provider decides you don't need to finish detox first, the Medication Guide says the shot may be given in a medical facility that can treat sudden withdrawal.¹

The injection visit and what to watch afterward

A provider mixes the powder with the liquid that comes in the carton and injects it deep into a buttock muscle. The carton has 1½-inch and 2-inch needles, and the provider picks one to fit your build, because a shot that lands under the skin instead of in the muscle may raise the chance of a severe reaction.¹ Vivitrol is not for self-injection; serious reactions, some needing a hospital stay, have been reported after people injected it themselves.¹

In the alcohol trials, 69% of people on Vivitrol had some injection-site reaction, against 50% on a placebo shot. Most were tenderness (45% vs 39%), hardening (35% vs 8%) or pain (17% vs 7%).¹ Since approval, there have been reports of abscesses, skin infection and tissue death (necrosis), some needing surgery and some leaving significant scars. Most were in women.¹

Call your provider right away if an injection site has intense pain, feels hard, swells over a large area, or develops lumps, blisters, an open wound or a dark scab. Also report any reaction that worries you, gets worse, or isn't better 2 weeks after the shot.¹

Nausea is the most common other side effect (33% vs 11% on placebo). It is usually mild, fades within a few days, and is less likely with later shots. Tiredness, headache, dizziness and less appetite are also common.¹ Label warnings also cover liver injury (hepatitis), depression and suicidal thoughts, an allergic type of pneumonia, and serious allergic reactions.¹ Rates, and what to do about each, are on naltrexone side effects.

When the block fades, a smaller opioid dose can be fatal

The block also affects medical care. Opioid pain relievers and opioid cough or diarrhea medicines may not work while you're on the shot. Carry a card or other note saying you get Vivitrol, and whenever you need medical care, tell the provider when your last shot was. Options for pain include regional numbing and non-opioid pain relievers.¹

Missed shots, restarting and stopping

• Missed a shot: get the next one as soon as you can.¹
• Restarting after a break: there are no data on restarting. You need to be opioid-free at the time of the shot.¹
• Coming from tablets: you don't need to take naltrexone tablets first, and there are no systematically collected data on switching from tablets to the shot.¹
• Stopping: you simply don't get the next shot, and levels fall over the following weeks. The overdose warning above applies. In the criminal justice trial, the benefit faded after the shots ended.^1,15

A shot costs about $1,700 to $1,760 before insurance

Three reference prices for the drug alone, checked for October 2026:

• Cash: from $1,758.09 per shot on Drugs.com.¹²
• What pharmacies pay (NADAC, data as of Oct 14, 2026): $1,716.11 per kit.²³
• Medicare Part B limit: $1,724.06 for 380 mg, October through December 2026 (billing code J2315, $4.537 per mg).²⁴

The clinic also charges to give the shot. We found no national figure for that fee, so ask before the first appointment.

Insurance and assistance.

• Medicare: Part B covers naltrexone given in a doctor's office or an opioid treatment program, according to Medicare.gov's opioid use disorder page. That page doesn't spell out the same coverage for alcohol use disorder.²⁵ Original Medicare coinsurance on the drug works out to about $332 a shot once the Part B deductible is met (our arithmetic from the CMS file).²⁴
• Medicaid: in 2023, 46 of 53 state fee-for-service Medicaid programs covered the shot.³ In a study of 2021 Medicaid managed care plans, 42.8% of plans that covered it required prior authorization or quantity limits.⁴
• Commercial insurance or none: Alkermes's co-pay program takes up to $500 off each prescription, up to $6,000 a year. It pays toward the drug only, not the injection or office visit, and it isn't open to people on Medicare, Medicaid or other government plans.^26,27

The unbranded Amneal version had no price we could find. The full breakdown, including a year of shots and the co-pay terms, is in the Vivitrol section of naltrexone cost.

How to get a Vivitrol shot

1. Find a prescriber. Naltrexone is not a controlled substance, and SAMHSA says it "can be prescribed and administered by any practitioner licensed to prescribe medications."^5,11

2. Expect a specialty pharmacy step. The drug often ships from a pharmacy to the clinic in a refrigerated package.¹³ Alkermes tells patients to expect a call from the pharmacy to confirm shipping, co-pay card and payment details, and to answer it to avoid delays. You then get the shot at your provider's office.²⁸

3. Use a locator. On SAMHSA's FindTreatment.gov, facility listings include a medications field that can show "Naltrexone (extended-release, injectable)."²⁹ Alkermes runs its own provider locator (or call 1-800-VIVITROL). Providers sign up voluntarily, and a listing is not an endorsement.³⁰ See Vivitrol shot near me.

4. Online programs. Few offer the shot, which a provider has to give in person. Of the online programs in our database, Boulder Care lists Vivitrol among its alcohol medicines but doesn't explain how the injection is arranged. Rezolv Health, in California, Washington and Nevada, says the monthly injection is given in person or in an office and that your provider coordinates it.^6,7 Workit Health, Talkspace and Oar Health say they don't offer it.^31-33 All programs are compared on where to get naltrexone online.

Questions to ask a clinic before your first visit:

1. Do you give Vivitrol here, and do you stock it or order it from a specialty pharmacy?
2. What do you charge to give the shot, and will you handle prior authorization with my plan?
3. How do you confirm I'm opioid-free: a urine test, a naloxone challenge, or both?
4. Will you prescribe naloxone or nalmefene for me to keep at home?
5. What counseling or support comes with the shot?

Who shouldn't get Vivitrol

You can't get the shot if you¹:

• take opioid pain medicines or other opioids, or are physically dependent on opioids
• are in opioid withdrawal
• failed a naloxone challenge test or had a positive urine test for opioids
• are allergic to naltrexone, the polymer in the microspheres, or the ingredients of the mixing liquid (such as carboxymethylcellulose)

Talk it through first if you¹:

• have liver disease
• have hemophilia, another bleeding problem or low platelets
• have moderate or severe kidney disease (not studied)
• are pregnant or planning to be (the risk is unknown) or breastfeeding

Had the Vivitrol shot? Share what it was like, or read other people's naltrexone reviews.

How we checked

• Label facts come from the current Vivitrol prescribing information and Medication Guide (May 2026); the approval history comes from the 2010 label and FDA records.^1,8,9
• Evidence comes from three opioid trials and the main alcohol trial (abstracts), two meta-analyses, the 2023 federal review and the VA/DoD guideline.^{2,14-16,18-21}
• Prices, coverage and online programs were checked October 17, 2026. Alkermes's pages were used only for co-pay terms, prescription steps and the locator.^26,28,30