Naltrexone and bupropion

Name: Naltrexone and bupropion

Commonly used brand name(s)

In the U.S.

  • Contrave

Available Dosage Forms:

  • Tablet, Extended Release

Therapeutic Class: Antiobesity Agent

Pharmacologic Class: Naltrexone

Chemical Class: Bupropion

What are some things I need to know or do while I take Naltrexone and Bupropion?

  • Tell all of your health care providers that you take this medicine. This includes your doctors, nurses, pharmacists, and dentists.
  • Follow the diet and workout plan that your doctor told you about.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take naltrexone and bupropion.
  • This medicine may cause high blood pressure.
  • Check blood pressure and heart rate as the doctor has told you. Talk with the doctor.
  • If you have high blood sugar (diabetes), you will need to watch your blood sugar closely.
  • This medicine may raise the chance of seizures. The chance may be higher in people who have certain health problems, use certain other drugs, or drink a lot of alcohol. Talk to your doctor to see if you have a greater chance of seizures while taking this medicine.
  • Avoid drinking alcohol while taking naltrexone and bupropion.
  • Talk with your doctor before you use other drugs and natural products that slow your actions.
  • If you are taking digoxin, talk with your doctor. You may need to have your blood work checked more closely while you are taking it with this medicine.
  • Some people may have a higher chance of eye problems with naltrexone and bupropion. Your doctor may want you to have an eye exam to see if you have a higher chance of these eye problems. Call your doctor right away if you have eye pain, change in eyesight, or swelling or redness in or around the eye.
  • Talk with your doctor before taking opioid drugs like some cough and cold products, some diarrhea drugs, and some pain drugs. These drugs may not work as well. Do not take more of these drugs to try to get them to work better. Doing this may cause very bad injury, coma, or death. Talk with your doctor.
  • People taking this medicine may get more effects from opioid drugs when naltrexone and bupropion is stopped. Even low doses of opioid drugs may cause very bad and sometimes deadly effects in these people. Talk with your doctor.
  • If you are addicted to pain drugs and are given this medicine, you may have signs of withdrawal. Talk with your doctor.
  • This medicine is not approved to treat mental or mood problems like low mood (depression) or to help stop smoking. When another bupropion drug was used to stop smoking, mental or mood problems happened or got worse. Talk with the doctor.
  • If you are 65 or older, use naltrexone and bupropion with care. You could have more side effects.
  • This medicine may cause harm to the unborn baby if you take it while you are pregnant. If you are pregnant or you get pregnant while taking this medicine, call your doctor right away.

How is this medicine (Naltrexone and Bupropion) best taken?

Use naltrexone and bupropion as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Swallow whole. Do not chew, break, or crush.
  • Take by mouth only. Do not inject or snort this medicine. Doing so can cause very bad side effects like seizures and death.
  • Avoid taking naltrexone and bupropion with high-fat meals.
  • If you have trouble swallowing, talk with your doctor.
  • To gain the most benefit, do not miss doses.
  • Keep taking this medicine as you have been told by your doctor or other health care provider, even if you feel well.
  • Do not take naltrexone and bupropion more often than you are told. This may raise the risk of seizures. Be sure you know how far apart to take your doses.

What do I do if I miss a dose?

  • Skip the missed dose and go back to your normal time.
  • Do not take 2 doses at the same time or extra doses.

Brand Names U.S.

  • Contrave


Naltrexone is a pure opioid antagonist, and bupropion is a relatively weak inhibitor of the neuronal reuptake of dopamine and norepinephrine. The exact neurochemical effects of naltrexone/bupropion leading to weight loss are not fully understood. Effects may result from action on areas of the brain involved in the regulation of food intake: the hypothalamus (appetite regulatory center) and the mesolimbic dopamine circuit (reward system).

Dosing Hepatic Impairment

Maximum dose: One tablet (naltrexone 8 mg/bupropion 90 mg) daily

How should this medicine be used?

The combination of naltrexone and bupropion comes as an extended-release (long-acting) tablet to take by mouth. It is usually taken twice a day. Do not take this medication with a high-fat meal. Take naltrexone and bupropion at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take naltrexone and bupropion exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the extended-release tablets whole; do not split, chew, or crush them.

Your doctor will probably start you on a low dose of the combination of naltrexone and bupropion and gradually increase your dose, not more than once every week, for 4 weeks. After 16 weeks of treatment, your doctor will check to see how much weight you have lost. If you have not lost a certain amount of weight, your doctor may tell you to stop taking the combination of naltrexone and bupropion as it is unlikely that you will benefit from continuing your treatment.

What should I do if I forget a dose?

Skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.