Naltrexone (By injection)

Naltrexone (nal-TREX-one)

Helps prevent alcohol or drug abuse relapse.

Brand Name(s):

Vivitrol

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. You should not receive it if you had an allergic reaction to naltrexone, polylactide-co-glycolide (PLG), or carboxymethylcellulose, or if you have a physical drug dependence or withdrawal symptoms to narcotic medicines.

How to Use This Medicine:

Injectable

• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot into one of your muscles.
• An overdose to a narcotic medicine can be dangerous. Follow directions carefully so you do not get too much medicine at one time. Your doctor may also give naloxone to treat an overdose.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: Call your doctor or pharmacist for instructions.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• You should not receive this medicine if you are also receiving a narcotic pain medicine.
• Some medicines can affect how naltrexone works. Tell your doctor if you are using cough and cold medicine, or diarrhea medicine.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, lung or breathing problems, bleeding problems (including hemophilia), or a history of depression.
• This medicine may cause the following problems:
  • High risk of narcotic medicine overdose, which can lead to death
  • Serious injection site reactions
  • Liver problems
  • Lung problem, including eosinophilic pneumonia
  • Unusual thoughts or behavior
• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
• Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Anxiety, depression, or unusual thoughts and behaviors, thoughts of killing yourself or others
• Chest pain or trouble breathing
• Dark urine or pale stools, nausea, vomiting, loss of appetite, pain in your upper stomach, yellow skin or eyes
• Dizziness, drowsiness, or fainting
• Extreme dizziness or weakness, shallow breathing, slow or uneven heartbeat, sweating, cold or clammy skin, seizures
• Fast, slow, or pounding heartbeat
• Fever, chills, cough, runny or stuffy nose, sore throat, body aches
• Pain, itching, burning, swelling, or a lump under your skin where the shot was given
• Trouble sleeping, getting upset easily, a big increase in energy, or reckless behavior

If you notice these less serious side effects, talk with your doctor:

• Back, muscle, or joint pain
• Change in appetite
• Constipation, diarrhea, or stomach pain

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 12/4/2023