Vivitrol (naltrexone) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it for the following uses in adults:

  • To treat alcohol dependence (also called alcohol use disorder). Vivitrol is approved to help prevent people from consuming alcohol after they’ve quit drinking.
  • To treat opioid dependence (also called opioid use disorder). Vivitrol is approved to help prevent people from taking opioids after they’ve stopped taking them.

Vivitrol is a long-term treatment for alcohol dependence and opioid dependence. It’s prescribed as part of a complete treatment program. This program includes counseling or other types of therapy and support.

Here are some fast facts about Vivitrol:

  • Active ingredient: naltrexone
  • Drug class: opioid antagonist
  • Drug form: liquid suspension given as an intramuscular injection by a healthcare professional

Like other drugs, Vivitrol can cause side effects. Read on to learn about potential common, mild, and serious side effects. For a general overview of Vivitrol, including details about its uses, see this article.

Vivitrol injections (shots) can cause certain side effects, some of which are more common than others.

More common side effects in people receiving Vivitrol for alcohol dependence include:

More common side effects in people receiving Vivitrol for opioid dependence include:

Vivitrol is a long-acting injection. Its effects can last for at least a month. If you have side effects after receiving Vivitrol, they may get better after a few days or weeks. But some side effects may continue after a month, until the injection wears off. If side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who received Vivitrol in clinical trials. These side effects can vary, depending on which condition the drug is being used to treat.

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Vivitrol treatment. This list doesn’t include all the possible mild side effects of the drug. For more information, you can refer to Vivitrol’s prescribing information.

Mild side effects that have been reported with Vivitrol include:

Vivitrol is a long-acting medication. Its effects can last for at least a month. If you have side effects after receiving Vivitrol, they may be temporary, lasting a few days to weeks. But some side effects may continue after a month, until the injection wears off. If the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect during Vivitrol treatment and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.

Vivitrol may cause serious side effects. The list below may not include all the possible serious side effects of the drug. For more information, you can refer to Vivitrol’s prescribing information.

If you develop serious side effects during Vivitrol treatment, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* For more information about this side effect, see “Side effect specifics” below.

Vivitrol may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

What’s the expected timeline of Vivitrol side effects? Are any side effects long term?

Most of Vivitrol‘s side effects are short term. For example, nausea commonly occurs after the first injection, but it typically gets better within a few days. And nausea is less likely to occur with later injections.

Keep in mind that Vivitrol is a long-acting injection. Any side effects could last until the drug wears off, which takes at least a month.

Long-term side effects of Vivitrol are possible. They may include depression and liver injury, such as hepatitis (swelling in your liver). In most cases, this type of liver injury heals within a few months. However, if it’s not treated, hepatitis may cause long-term effects. Depression can be treated with medication and therapy.

These side effects aren’t long term in everyone who experiences them.

It’s not known if using Vivitrol long term increases your risk of side effects. If you have questions about Vivitrol’s side effects, talk with your doctor.

Does Vivitrol come as a pill? If so, what side effects does the pill form cause?

Vivitrol comes as an injection that contains the active ingredient naltrexone. It’s an extended-release (long-acting) form of naltrexone.

Vivitrol is given once a month as an intramuscular injection by your doctor or another healthcare professional.

Naltrexone is also available in an oral tablet or pill form. Naltrexone tablets are a short-acting form of the drug that’s taken once a day.

Naltrexone tablets can cause similar side effects to Vivitrol. However, since naltrexone tablets are taken by mouth, they don’t cause injection site reactions. Also, pneumonia due to an allergic reaction, a side effect of Vivitrol, hasn’t been reported with the tablets. (To learn more about this side effect, see the “Side effect specifics” section below.)

It’s also important to note that naltrexone tablets only last in your body for about 1 or 2 days. Whereas a Vivitrol injection lasts for at least a month. So, if you have side effects after taking naltrexone tablets, they may not last as long as the side effects of Vivitrol injections.

If you’re interested in taking naltrexone tablets instead of having Vivitrol injections, talk with your doctor. They can help you determine which form of naltrexone may be more suitable for you.

What are Vivitrol’s side effects when it’s prescribed for alcohol dependence?

Vivitrol can have similar side effects when it’s prescribed for alcohol dependence or opioid dependence. However, some side effects were more common in people who received Vivitrol for alcohol dependence in clinical trials. For details about these side effects, see the “More common side effects of Vivitrol” section above.

If you’re concerned about side effects while receiving Vivitrol for alcohol dependence, talk with your doctor.

Can Vivitrol cause erectile dysfunction?

Possibly. Sexual side effects, including erectile dysfunction (ED) and delayed ejaculation have been reported with naltrexone tablets. Naltrexone is the active ingredient in Vivitrol. So, it’s possible to have ED with Vivitrol treatment. However, ED wasn’t specifically reported in clinical trials of Vivitrol. Other sexual side effects, such as reduced sex drive, were reported.

Also, it’s important to note that alcohol dependence or opioid dependence* can also cause sexual problems, such as ED. If you have sexual problems during Vivitrol treatment, talk with your doctor. They can recommend ways to treat them.

* Vivitrol is approved to treat these conditions. To learn more, see this article.

Does stopping Vivitrol treatment cause withdrawal?

No. Vivitrol doesn’t have a risk of misuse (abuse) or dependence. So, stopping Vivitrol treatment won’t cause withdrawal. (With withdrawal, you may experience physical and psychological symptoms after you reduce or stop taking certain substances. These include alcohol or certain drugs.)

Vivitrol is a drug that’s prescribed to treat alcohol dependence or opioid dependence. (To learn more about the approved uses of Vivitrol, see this article.) The drug works to prevent people who’ve stopped taking these substances from misusing them again.

If you have questions about Vivitrol and withdrawal, talk with your doctor.

Learn more about some of the side effects that Vivitrol may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Vivitrol.

Injection site reaction

Some people may have an injection site reaction after receiving Vivitrol. (The drug is given as an intramuscular injection into your buttock by your doctor or another healthcare professional. To learn more, see this article.) In clinical trials, injection site reactions were common during Vivitrol treatment.

Injection site reactions to Vivitrol are usually mild. They may cause the following symptoms around the site where you have your shot:

Injection site reactions can become severe. Some people developed severe swelling, infection, abscess, and dead skin at their injection site. In rare cases, surgery was needed to remove dead skin. This led to severe scarring.

What you can do

It’s important that Vivitrol is given by your doctor or another healthcare professional. They will use the correct needle and injection technique to give your doses. This will help minimize the risk of injection site reactions. Do not try to administer Vivitrol yourself. (You may sometimes need to collect the medication from a pharmacy and bring it to your doctor’s office.)

If you have an injection site reaction that’s bothersome, severe, doesn’t get better after a few days, or worsens, talk with your doctor. They will determine if the reaction needs to be treated.

Depression

Some people may have depression that could lead to suicidal thoughts or behavior during Vivitrol treatment. In clinical trials, depression was common with Vivitrol, but suicidal thoughts or behavior were rare.

It’s important to note alcohol dependence or opioid dependence may also increase your risk of depression and suicidal thoughts. (Vivitrol is approved to treat these conditions. To learn more, see this article.)

Symptoms of depression may include:

What you can do

Consider telling your family or close friends that you’re receiving Vivitrol treatment. You can explain that your new medication might raise the risk of suicidal behavior or thoughts. This way, you and the people close to you can watch for any changes in your mood or behavior during your treatment.

If you have symptoms of depression, or any other changes in your mood or behavior, talk with your doctor right away. They can help you get treatment. They may also recommend stopping Vivitrol treatment.

If you have suicidal thoughts, it’s important to get help right away.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Ask the tough question: “Are you considering suicide?”
  • Listen to the person without judgment.
  • Call 911 or the local emergency number, or text TALK to 741741 to communicate with a trained crisis counselor.
  • Stay with the person until professional help arrives.
  • Try to remove any weapons, medications, or other potentially harmful objects if it’s safe to do so.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The 988 Suicide and Crisis Lifeline is available 24 hours a day at 988. During a crisis, people who are hard of hearing can use their preferred relay service or dial 711 then 988.

Find more links and local resources.

Liver damage

Hepatitis (liver inflammation) or liver damage may occur during Vivitrol treatment. However, these side effects weren’t common in clinical trials of the drug.

Liver damage can be detected with blood tests called liver function tests (LFTs). They measure the levels of liver enzymes in your blood. Liver enzymes are proteins that help your liver carry out its normal function. If you have liver damage, these proteins can be present in your blood. If LFTs show high levels of liver enzymes, you may have liver damage.

Liver damage can also cause certain symptoms. These may include:

It’s important to note that heavy alcohol consumption can also cause liver damage. If you have alcoholic liver disease, Vivitrol treatment could worsen your liver problem. Talk with your doctor about whether Vivitrol is right for you.

What you can do

Your doctor will order LFTs to check the health of your liver during Vivitrol treatment. Be sure to keep your appointments for these blood tests. And if you have symptoms of liver damage during Vivitrol treatment, see your doctor right away. They may order extra LFTs to check your liver function.

If your doctor determines that Vivitrol is affecting your liver, they’ll likely stop your treatment with this drug. Talk with your doctor about suitable alternatives. (To learn more about alternatives, see this article.)

Nausea

Some people may have nausea after receiving their Vivitrol injections. In clinical trials, nausea was common with Vivitrol treatment.

You’re most likely to have nausea after your first injection of Vivitrol. This usually gets better after a few days. You’re less likely to have nausea after later injections.

What you can do

If you have nausea that’s bothersome after receiving Vivitrol, talk with your doctor. They can recommend ways to help reduce this side effect.

Weight gain

Weight gain may occur during your Vivitrol treatment. In clinical trials, both weight gain and weight loss were reported with Vivitrol treatment. However, they were not common.

Some people who misuse (abuse) opioids or alcohol may not eat properly. If you receive Vivitrol treatment for alcohol dependence or opioid dependence, you may gain weight. This may happen because you’re eating more healthily as a result of your treatment program.

However, some people receiving Vivitrol may lose weight because the drug can reduce appetite as a side effect.

What you can do

During your Vivitrol treatment, talk with your doctor about your diet and nutrition. If you’re concerned about gaining or losing weight, talk with your doctor. They can suggest ways to improve your diet and maintain a weight that’s healthy for you.

Allergic reaction

Like most drugs, Vivitrol can cause an allergic reaction in some people.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep receiving Vivitrol. But if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Be sure to talk with your doctor about your health history before starting Vivitrol treatment. This drug may not be right for you if you have certain medical conditions or other factors that affect your health. The conditions and factors to consider include:

Allergic reaction. If you’ve had an allergic reaction to Vivitrol or any of its ingredients, your doctor will likely not prescribe you Vivitrol. Ask them what other medications may be better options for you.

Recent use of opioids. Vivitrol works by blocking the effects of opioids in your body.* If you’ve taken opioids in the 2 weeks before starting Vivitrol treatment, the drug could cause opioid withdrawal symptoms.† (With withdrawal, you may experience physical and psychological symptoms after you reduce or stop taking certain substances.) These symptoms could be severe enough to need treatment in a hospital.

Before receiving an injection of Vivitrol, be sure to tell your doctor if you’ve recently taken opioids. Your doctor won’t give you Vivitrol if you’re currently misusing (abusing) opioids or taking opioid pain relievers. And they won’t give you Vivitrol if you’re physically dependent on opioids or have symptoms of opioid withdrawal.

Bleeding problems. Having a blood disorder or bleeding problem, such as hemophilia, may increase your risk of bleeding after Vivitrol injections. Talk with your doctor if you have any bleeding problems or conditions that affect your blood. They might recommend a treatment other than Vivitrol.

Liver problems. Vivitrol causes liver problems. If you already have liver problems or if you drink a lot of alcohol, your risk for liver problems with Vivitrol may be higher. Talk with your doctor about any liver problems you have before you start Vivitrol treatment.

Kidney problems. It isn’t known whether it’s safe to take Vivitrol if you have moderate or severe kidney problems. Your doctor will determine if Vivitrol treatment is safe for you.

* To learn more about how Vivitrol works, see this article.
† For more details about this side effect, see the “Serious side effects of Vivitrol” section above.

Risk of opioid overdose

If you have opioid dependence, you could have an increased risk of opioid overdose if you take opioids during Vivitrol treatment.

Vivitrol works by blocking the effects of opioids in your body. So, if you take opioids during Vivitrol treatment, you won’t get a “high” feeling from the opioid. However, if you take larger doses of opioids to try and get high, this could lead to opioid overdose. In rare cases, it could even lead to death.

Also, if you take opioids while the effect of Vivitrol is wearing off, your body may be more sensitive to opioids than it was before treatment. (Vivitrol is a long-acting injection. It can take at least a month for its effects to wear off.) This can happen:

  • just before your next dose is due
  • after missing a dose of Vivitrol
  • after stopping Vivitrol treatment

If you take opioids at these times, even in small doses, it could cause accidental overdose or death.

If you’re concerned about your risk of opioid overdose during Vivitrol treatment, talk with your doctor. They may prescribe you the drug Narcan (naloxone) to keep available in case of opioid overdose. (Narcan is a nasal spray that a caregiver can administer to reverse an opioid overdose.)

Alcohol use and Vivitrol

Vivitrol is a drug that’s prescribed to treat alcohol dependence or opioid dependence. (To learn more about the approved uses of Vivitrol, see this article.)

If you’re prescribed Vivitrol for alcohol dependence, the drug is meant to help you avoid consuming alcohol after you’ve quit drinking. So, you should not be drinking alcohol during Vivitrol treatment for this condition. Be sure to follow the treatment program that your doctor recommends.

If you receive Vivitrol for opioid dependence, your doctor will likely recommend that you avoid drinking alcohol during the treatment.

Alcohol isn’t known to interact with Vivitrol. But you may have an increased risk of Vivitrol side effects if you drink alcohol during the treatment. These include:

You may also have an increased risk of liver damage. This is because both drinking alcohol and having Vivitrol treatment can affect your liver. (For details, see the “Side effect specifics” section above.)

If you have questions about alcohol use and Vivitrol treatment, talk with your doctor.

Pregnancy and breastfeeding during Vivitrol treatment

It’s not known if Vivitrol injections are safe to receive during pregnancy. The treatment hasn’t been studied during pregnancy.

The effect of naltrexone tablets during pregnancy has been studied in animals. (Naltrexone is the active ingredient in Vivitrol). In these studies, pregnant animals that were given naltrexone had an increased risk of pregnancy loss. Naltrexone didn’t increase the risk of congenital anomalies (also known as birth defects) in these studies. But keep in mind that animal studies don’t always reflect what will happen in humans.

It’s important to note that misusing (abusing) alcohol or opioids during pregnancy can harm your child. If you have alcohol dependence or opioid dependence, Vivitrol treatment can help prevent you from misusing these substances. If you’re pregnant or planning to become pregnant, talk with your doctor and the risks and benefits of Vivitrol treatment.

Vivitrol is known to pass into breast milk. However, it’s not known what effect the drug may have on a breastfed child. If you’re breastfeeding or plan to breastfeed, talk with your doctor about the best way to feed your child during your Vivitrol treatment.

Vivitrol causes some common side effects, but these are usually mild and easily managed. Vivitrol can also cause some more serious side effects.

If you’d like to learn more about Vivitrol, talk with your doctor or pharmacist. They can help answer any questions you have about side effects of the drug.

Besides talking with your doctor, you can do some more research on your own. These articles might help:

  • More information about Vivitrol. For details about other aspects of Vivitrol, refer to this article.
  • Dosage information. To read about Vivitrol’s dosages and how it’s given, see this article.
  • Drug comparison. To learn how Vivitrol compares with Sublocade, see this article.
  • A look at your condition. For details about dependence on alcohol or opioids, this list of articles may be helpful.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.