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Generic Name: naltrexone (injection) (nal TREX own)
Brand Names: Vivitrol

Medically reviewed by Judith Stewart, BPharm Last updated on Apr 2, 2020.

What is Vivitrol?

Vivitrol (naltrexone) blocks the effects of opioid medication, including pain relief or feelings of well-being that can lead to opioid abuse. An opioid is sometimes called a narcotic. Vivitrol is used as part of a treatment program for drug or alcohol dependence.

Vivitrol injection is used to prevent relapse in people who became dependent on opioid medicine and then stopped using it. Naltrexone can help keep you from feeling a "need" to use the opioid.

Vivitrol injection is also used to treat alcoholism by reducing your urge to drink alcohol. This may help you drink less or stop drinking altogether. Naltrexone will not decrease the effects of alcohol you recently consumed. You should not be drinking at the time you receive your first Vivitrol injection.

Naltrexone is not a cure for drug addiction or alcoholism.

Important information

You should not receive Vivitrol if you are having drug or alcohol withdrawal symptoms, if you have taken any opioid medicine within the past 2 weeks, or if you are still actively drinking alcohol.

Call your doctor at once if you have signs of liver problems - nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes).

Vivitrol can cause liver damage, especially at high doses. You should not receive Vivitrol injection if you have hepatitis or symptoms of liver failure.

Before receiving Vivitrol

You should not receive a Vivitrol injection if you still use opioid medicine, or you could have sudden and severe withdrawal symptoms.

You should not receive Vivitrol if you are allergic to naltrexone, or if:

  • you are having withdrawal symptoms from drug or alcohol addiction;

  • you have used any opioid medicine within the past 10 days (including fentanyl, Vicodin, OxyContin, and many others); or

  • you have used methadone or buprenorphine (Subutex, Butrans, Suboxone, Zubsolv) in the past 14 days.

To make sure Vivitrol is safe for you, tell your doctor if you have:

  • liver disease;

  • kidney disease; or

  • a bleeding or blood-clotting disorder such as hemophilia.

It is not known whether Vivitrol will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Naltrexone can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

How is Vivitrol used?

Vivitrol is injected into a muscle. This injection is usually given once a month (every 4 weeks) and can be given only by a doctor or nurse in a clinic.

It is important to receive your Vivitrol regularly to get the most benefit.

You may notice pain, redness, bruising, swelling, or a hard lump where the medicine was injected. Call your doctor if you have this type of reaction to the shot, especially if it does not clear up or gets worse within 2 weeks.

Vivitrol injections are only part of a complete treatment program that may also include additional forms of counseling and/or monitoring. Follow your doctor's instructions very closely.

Wear a medical alert tag or carry an ID card stating that you use Vivitrol. Any medical care provider who treats you should know that you are receiving this medication. If you need surgery, tell the surgeon ahead of time that you are receiving Vivitrol injections.

After receiving Vivitrol, your body will be more sensitive to opioids. If you use an opioid medicine in the future, you will need to use less than before Vivitrol treatment. Using the same amount you used before could lead to overdose or death.

Vivitrol dosing information

Usual Adult Dose for Alcohol Dependence:

Oral Tablets:
50 mg orally once a day

Extended-release injectable suspension:
380 mg every 4 weeks (or once a month) via intramuscular gluteal injection, alternating buttocks

Usual Adult Dose for Opiate Dependence:

Treatment should not be attempted unless the patient has remained free of opioids for at least 7 to 10 days. Opioid abstinence should be verified by analysis of urine for absence of opioids. The patient should not be manifesting withdrawal signs or reporting withdrawal symptoms. If there is any question of occult opioid dependence, perform a naloxone challenge test and do not initiate naltrexone therapy until the naloxone challenge is negative. The naloxone challenge test should not be performed in a patient showing clinical signs or symptoms of opioid withdrawal, or whose urine contains opioids. The naloxone challenge can be repeated in 24 hours.

Initial dose: 25 mg orally one time.
Maintenance dose: If no withdrawal signs occur, 50 mg orally once a day may be started.
Alternative dose schedules: (to improve compliance) 50 mg orally on week days and 100 mg orally on Saturday; or 100 mg orally every other day; or 150 mg orally every third day.

Extended-release injectable suspension: 380 mg every 4 weeks (or once a month) via intramuscular gluteal injection, alternating buttocks

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment to receive your Vivitrol injection.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Vivitrol?

Do not use narcotic medication, heroin, or other street drugs while you are receiving Vivitrol. Never try to overcome the effects of Vivitrol by taking large doses of opioids. Doing so could result in dangerous effects, including coma and death.

Do not drink alcohol during treatment with Vivitrol.

Ask your doctor before using any medicine to treat a cold, cough, diarrhea, or pain. These medicines may contain narcotics or alcohol.

Vivitrol may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you.

Vivitrol side effects

Get emergency medical help if you have signs of an allergic reaction to Vivitrol: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Using opioid medicine while you are receiving Vivitrol injections could stimulate opioid withdrawal symptoms. Common withdrawal symptoms are yawning, irritability, sweating, fever, chills, shaking, vomiting, diarrhea, watery eyes, runny nose, goose bumps, body aches, trouble sleeping, and feeling restless.

Call your doctor at once if you have:

  • weak or shallow breathing;

  • confusion, severe dizziness, feeling like you might pass out;

  • depression, thoughts about suicide or hurting yourself;

  • severe pain, swelling, blistering, skin changes, a dark scab, or a hard lump where the medicine was injected;

  • new or worsening cough, wheezing, trouble breathing; or

  • liver problems - nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common Vivitrol ivitrol side effects may include:

  • nausea, vomiting, changes in appetite;

  • muscle cramps;

  • dizziness, drowsiness;

  • abnormal liver function tests;

  • sleep problems (insomnia);

  • stuffy nose, tooth pain; or

  • pain, swelling, or itching where the injection was given.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Vivitrol?

Vivitrol will block the effects of any narcotic medicines you take (such as prescription medicine for pain, cough, or diarrhea). Harmful side effects could also occur.

Other drugs may interact with naltrexone, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

  • Your doctor can provide more information about Vivitrol.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Vivitrol only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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