Contrave (Naltrexone and Bupropion) – Oral


This medication has a boxed warning, the Food and Drug Administration’s (FDA) strictest warning label, for the increased risk of suicidal thoughts and behaviors in people treated with antidepressants. Contrave contains bupropion, a member of an antidepressant class.

What Is Contrave?

Contrave (naltrexone and bupropion) is a prescription drug used along with diet and exercise for chronic (long-term) weight management in adults who are obese or overweight with at least one other weight-related condition.

Contrave contains two ingredients: naltrexone and bupropion. Naltrexone is in a drug class called opiate antagonists. Bupropion is an antidepressant. The ingredients in Contrave work on two areas of the brain called the hunger center and the reward system. They help reduce appetite and control cravings.

Contrave is available as an extended-release tablet. You take this medication by mouth.

Drug Facts

Generic Name: Naltrexone and bupropion

Brand Name(s): Contrave

Drug Availability: Prescription

Therapeutic Classification: Anti-obesity agent

Available Generically: No

Controlled Substance: N/A

Administration Route: Oral

Active Ingredient: Naltrexone and bupropion

Dosage Form: Extended-release tablet

What Is Contrave Used For?

The FDA approved Contrave to manage weight in adults who are either:

Contrave works by controlling appetite and cravings. If you are prescribed Contrave, your healthcare provider will likely also recommend lifestyle changes, such as diet and exercise, to help manage your weight.

Contrave has not been studied in combination with other weight-loss medications or supplements.

Contrave (Naltrexone and bupropion) Drug Information - Illustration by Dennis Madamba

Verywell / Dennis Madamba

How to Take Contrave

Before taking Contrave, read all of the patient information that comes with your prescription. Ask your doctor or pharmacist if you have any questions.

The target dose for Contrave is to take two tablets, two times a day. Take Contrave exactly as directed. Your healthcare provider will provide you with a dosing schedule.

When taking Contrave, try to remember to:

  • Not take more than two tablets at once
  • Avoid chewing, crushing, or breaking the tablets (swallow the tablets whole)
  • Avoid taking it with a high-fat meal, which can increase your chance of having a seizure

If your healthcare provider also prescribes an opioid pain medication, you may need to stop taking Contrave. Ask your provider for medical guidance. If you need to take a urine test for drug screening, Contrave may affect the results. Tell the staff at the lab that you take Contrave.

Additionally, let your healthcare provider know if you have not lost 5% or more of your starting weight after 16 weeks of treatment.


Store Contrave at room temperature (68–77 degrees Fahrenheit), away from heat, direct light, and moisture. Keep Contrave in its original labeled container and out of the reach of children and pets.

How Long Does Contrave Take to Work?

Many people who take Contrave can start to see weight loss at around four weeks. Your healthcare provider will evaluate your results at about 12–16 weeks of treatment.

What Are the Side Effects of Contrave?

This is not a complete list of side effects and others may occur. A medical professional can advise you on side effects. If you experience other effects, contact your pharmacist or a medical professional. You may report side effects to the FDA at or 800-FDA-1088.

Like other medications, Contrave may cause side effects. Let your healthcare provider know about any side effects you experience, especially if they worsen or do not go away.

Common Side Effects

The most common side effects of Contrave are:

  • Stomach problems: Pain, nausea, vomiting, constipation, or diarrhea
  • Headache 
  • Dizziness 
  • Insomnia 
  • Dry mouth 
  • Increased heart rate and blood pressure
  • Palpitations
  • Anxiety 
  • Flushing 
  • Tiredness 
  • Tremor 
  • Flu 
  • Ringing in the ears (tinnitus)
  • Urinary tract infection (UTI)
  • Excess sweating 
  • Irritability 
  • Altered taste
  • Muscle strain 
  • Rash 

Severe Side Effects

Call your healthcare provider right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Serious side effects and their symptoms can include the following:

  • Hypersensitivity reaction or anaphylaxis: Symptoms can include rash, hives, swelling around the lips, tongue, and face, and difficulty breathing. Get emergency medical help right away if you have these symptoms. 
  • Stevens-Johnson syndrome: Symptoms can include red or purple rash, blistering or peeling skin, sore throat, fever, burning eyes. These symptoms require emergency medical attention. 
  • Changes in mood or behavior: Contrave can cause worsening depression, as well as anxiety, panic attacks, trouble sleeping, agitation, and thoughts about suicide or self-harm. It can also cause thoughts of homicide. Stop taking Contrave and call your healthcare provider right away or get emergency medical attention if any of these symptoms occur. 
  • Slowed breathing: Contrave depresses the central nervous system (CNS). You may need emergency medical attention if you have slowed breathing, extreme drowsiness, or difficulty waking up.
  • Liver problems: Symptoms may include upper stomach pain, tiredness, yellowing of the skin or whites of the eyes, dark urine. 
  • Seizures: Symptoms include staring, confusion, jerking movements, and loss of consciousness. 
  • Severely high blood pressure: Symptoms may include a severe headache, blurry vision, fast heartbeat, and pounding in the neck or ears.
  • Glaucoma: Symptoms can include blurry or tunnel vision, seeing halos around lights, and eye pain or swelling. 
  • Manic episodes: Symptoms can include racing thoughts, increased energy, extreme happiness, risk-taking behavior, or being unusually irritable or talkative.

Long-Term Side Effects

Contrave can cause delayed or long-term side effects.

Some side effects may be mild, such as:

  • Muscle cramps
  • Joint pain
  • Menstrual irregularities
  • Anxiety
  • Flu
  • Ringing in the ears
  • Excess sweating
  • Irritability
  • Hair loss

Moderate delayed or long-term side effects can include: 

  • Constipation
  • Memory problems
  • Sexual problems (erectile dysfunction)
  • Dehydration
  • Vaginal bleeding
  • Liver problems

Some delayed or long-term side effects can be severe, such as:

  • Heart attack
  • Seizures
  • Severe skin reactions
  • High pressure in the eye
  • Gallbladder inflammation
  • Having suicidal thoughts and actions

Report Side Effects

Contrave may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Contrave Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (extended-release tablets):
    • For weight loss:
      • Adults—At first, one tablet in the morning taken on week 1. Your doctor will increase your dose to one tablet in the morning and one tablet in the evening on week 2. Then, two tablets in the morning and one tablet in the evening on week 3. On week 4, two tablets in the morning and two tablets in the evening.
      • Children—Use is not recommended.


In some cases, your healthcare provider may modify your treatment with Contrave. Contrave may also have significant drug interactions and dosage adjustments may be needed. Consult with your healthcare provider and make them aware of all medications you may be taking.

You may need a lower dose if you:

  • Are 65 years or older
  • Have moderate kidney problems
  • Have moderate liver problems

Contrave may not be the right treatment if you are:

  • Under 18 years old: Contrave has not been studied for safety and efficacy in children.
  • Pregnant or breastfeeding: Contact your healthcare provider if you become pregnant while taking Contrave or are breastfeeding.

Missed Dose

If you miss a dose of Contrave, try to take it as soon as you can. Skip the missed dose if it is almost time for the next dose. Do not take two doses together. Do not take more than four tablets in one day.

Overdose: What Happens If I Take Too Much Contrave?

Symptoms of overdose may include:

  • Seizure
  • Loss of consciousness
  • Rapid or pounding heartbeat
  • Seeing things or hearing voices that do not exist

Do not use opioid pain medications, methadone, heroin, or other street drugs while taking Contrave. The combination could be dangerous and cause coma and death.

What Happens If I Overdose on Contrave?

If you think you or someone else may have overdosed on Contrave, call your healthcare provider or the Poison Control Center at 800-222-1222.

If someone collapses or isn't breathing after taking Contrave, call 911 immediately.


Drug Content Provided and Reviewed by IBM Micromedex®

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant during therapy. If you think you have become pregnant while using this medicine, tell your doctor right away.

Do not take naltrexone and bupropion combination with a monoamine oxidase (MAO) inhibitor (eg, isocarboxazid [Marplan®], phenelzine [Nardil®], selegiline [Eldepryl®], tranylcypromine [Parnate®]). Do not start taking naltrexone and bupropion combination during the 2 weeks after you stop a MAO inhibitor. Wait 2 weeks after stopping naltrexone and bupropion combination before you start taking a MAO inhibitor. If you take them together or do not wait 2 weeks, you may have confusion, agitation, restlessness, stomach or bowel symptoms, a sudden high body temperature, an extremely high blood pressure, or severe seizures.

Do not use naltrexone and bupropion combination if you are also using Zyban® to quit smoking or Aplenzin® or Wellbutrin® for depression, because they also contain bupropion. Also, do not take this medicine if you are using or have used narcotic drugs (eg, buprenorphine, methadone, or other habit-forming painkillers) within the past 7 to 10 days.

This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. Make sure the doctor knows if you have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. Also tell the doctor if you have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared. If you or your caregiver notice any of these side effects, tell your doctor right away.

You have a higher risk of accidental overdose, serious injury, or death if you use heroin or any other narcotic medicine while you are being treated with naltrexone and bupropion combination. Also, naltrexone prevents you from feeling the effects of heroin if you use it.

Do not stop taking this medicine without checking first with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping it completely. This is to decrease the chance of having certain side effects when you stop the medicine, such as agitation, anxiety, dizziness, a feeling of constant movement of self or surroundings, headaches, increased sweating, nausea, trembling or shaking, trouble with sleeping or walking, or unusual tiredness.

Your blood pressure might get too high while you are using this medicine. This may cause headaches, dizziness, or blurred vision. You might need to measure your blood pressure at home. If you think your blood pressure is too high, call your doctor right away.

This medicine may cause a serious type of allergic reaction called anaphylaxis, which can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash, itching, swelling of the face, tongue, or throat, trouble breathing, or chest pain.

Serious skin reactions (eg, Stevens-Johnson syndrome) can occur with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, red skin lesions, severe acne or skin rash, sores or ulcers on the skin, or fever or chills with this medicine.

Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellow eyes or skin. These could be symptoms of a serious liver problem.

Check with your doctor right away if blurred vision, eye pain, or any other change in vision occurs during or after treatment. Your doctor may want your eyes be checked by an ophthalmologist (eye doctor).

This medicine may increase the risk of hypoglycemia (low blood sugar) in patients with diabetes. Low blood sugar must be treated before it causes you to pass out (unconsciousness). People feel different symptoms of low blood sugar. It is important that you learn which symptoms you usually have so you can treat it quickly. You should check your blood sugar before you start treatment and while you are taking this medicine.

Drinking alcoholic beverages should be limited or avoided, if possible, with this medicine.

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Contrave?

Contrave is not appropriate for everyone. You should not take Contrave if you are allergic to naltrexone, bupropion, or any of the inactive ingredients in Contrave.

There are other reasons that it can be unsafe to take Contrave. These reasons include:

  • Use of a drug in a class called monoamine oxidase inhibitors (MAOIs) within 14 days
  • End-stage kidney disease
  • Uncontrolled high blood pressure (hypertension)
  • Seizure disorder or history of seizures
  • Anorexia or bulimia (eating disorders)
  • Opioid use, dependence, or acute opioid withdrawal
  • Use of another drug that contains bupropion (such as Wellbutrin)
  • Alcohol use 
  • Abruptly stopping use of alcohol, a benzodiazepine drug, sedative drug, or antiepileptic drug

With other medical conditions, you may still be able to use Contrave with caution. Your healthcare provider may closely monitor your treatment in these cases. Make sure to talk to your provider about your medical history. They will determine whether you can safely use Contrave.

Interactions: What Other Medications Should I Avoid?

Before taking Contrave, tell your healthcare provider about all of the medications you take, including prescription and over-the-counter (OTC) drugs, vitamins, and supplements.

MAOIs and opioid pain medications are among the standard drug interactions with Contrave. 

Combining Contrave with an MAOI drug can cause high blood pressure. Separate taking these drugs by at least 14 days.

If opioid medication is required, your healthcare provider may temporarily stop your Contrave treatment. You may restart the medication with caution seven to 10 days after stopping the opioid. 

Examples of other drugs that can interact with Contrave include:

  • Alcohol
  • Amantadine (available under the brand names Gocovri, Osmolex ER, and Symmetrel)
  • Antipsychotics, such as Risperdal (risperidone) and Haldol (haloperidol), among others
  • Beta-blockers, such as Lopressor (metoprolol), among others
  • Plavix (clopidogrel) 
  • Digoxin (available under the brand names Lanoxin, Cardoxin, Digitek, Digox, and Lanoxicas)
  • Human immunodeficiency virus (HIV) drugs, including Sustiva (efavirenz) and Kaletra (lopinavir and ritonavir)
  • Inbrija (levodopa) 
  • Selective serotonin reuptake inhibitor antidepressants, such as Lexapro (escitalopram) and Prozac (fluoxetine), among others
  • Theophylline, which is available under brand names, such as Elixophyllin, Norphyl, and Theo-24, among others
  • Tricyclic antidepressants, such as Elavil (amitriptyline) and Aventyl (nortriptyline), among others
  • Type 1C antiarrhythmic drugs, such as Tambocor (flecainide) and Rythmol (propafenone), among others

This is not a full list of drug interactions. Consult your healthcare provider for medical advice regarding drug interactions with Contrave.

What Medications Are Similar?

Besides Contrave, other drugs used for weight loss include:

  • Xenical (orlistat): An oral medication available by prescription
  • Alli (orlistat): A lower dose of orlistat available OTC
  • Qsymia (phentermine and topiramate): An oral prescription medication
  • Saxenda (liraglutide): A daily injectable prescription medication
  • Wegovy (semaglutide): A weekly injectable prescription medication
  • Oral appetite suppressants such as phentermine and diethylpropion: Available by prescription and indicated for short-term use of up to 12 weeks

There is also a variety of dietary supplements that advertise weight loss. However, the FDA does not regulate these supplements. Many of these products are unsafe with certain medical conditions and/or other medications. Always ask your healthcare provider before using any weight loss supplement.

This list is a list of drugs also prescribed for weight loss. It is not a list of drugs recommended to take with Contrave. Ask your pharmacist or a healthcare practitioner if you have questions.

Frequently Asked Questions

  • What is Contrave used for?

    The FDA approved Contrave for long-term weight management in adults who are obese or overweight with at least one other weight-related condition such as high cholesterol, high blood pressure, or type 2 diabetes. Contrave is used along with diet and exercise.

  • How does Contrave work?

    Contrave contains two ingredients: naltrexone and bupropion. The drugs work in the brain to reduce hunger and control cravings.

  • What drugs should not be taken with Contrave?

    Many drugs can interact with Contrave, such as MAOIs, opioid pain medicines, certain antidepressants, antipsychotics, and beta-blockers, among others. Before taking Contrave, review your medication list with your healthcare provider to ensure Contrave is safe for you. 

  • How long does it take for Contrave to work?

    Contrave may start to work in as soon as four weeks. Your healthcare provider will evaluate results at about 12–16 weeks of treatment with Contrave. If you have not lost 5% or more of body weight, your provider may advise you to stop taking Contrave. 

  • What are the side effects of Contrave?

    The most common side effects of Contrave are stomach pain, nausea, vomiting, and constipation or diarrhea. Other common side effects may include headache, insomnia, dizziness, dry mouth, anxiety, palpitations, and increased heart rate and blood pressure. Other side effects may occur. Ask your healthcare provider for a complete list of side effects.

  • How do I safely stop taking Contrave?

    Your healthcare provider will advise you on how long to take Contrave.

How Can I Stay Healthy While Taking Contrave?

Some people have thoughts of suicide when taking bupropion, an ingredient in Contrave. Make sure that you and your family, friends, and caregivers monitor any behavior changes while using this medication. If any changes occur, seek medical attention right away.

In addition to taking your medication, try to incorporate diet and exercise changes into your weight-management plan. Talk to your healthcare provider about what kind of diet and exercise might be appropriate for you.

Try to avoid consuming alcohol and high-fat meals while taking Contrave, as they can increase the risk of seizures. 

Before taking Contrave, discuss your medical history with your healthcare provider. Tell your provider about all the medications you take. When taking Contrave, follow your provider’s instructions for use. Do not take any other weight-loss medications or supplements unless your provider tells you to do so.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare professional. Consult your doctor before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine. DailyMed. Label: Contrave Extended-Release- naltrexone hydrochloride and bupropion hydrochloride tablet, extended release.

  2. MedlinePlus. Naltrexone and Bupropion.

  3. Epocrates. Contrave Entire Monograph.

  4. Prescribers’ Digital Reference. Contrave (bupropion hydrochloride/naltrexone hydrochloride) - Drug Summary.

  5. National Institute of Diabetes and Digestive and Kidney Diseases. Prescription Medications to Treat Overweight & Obesity.

By Karen Berger, PharmD
Karen Berger, PharmD, is a community pharmacist and medical writer/reviewer.