What is Naltrexone and Bupropion: Uses, Dosage, Side Effects and More

Naltrexone and bupropion is a prescription medication that combines two drugs to help with weight management. This combination works by affecting brain chemicals that control appetite and food cravings, making it easier for you to eat less and feel satisfied with smaller portions.

Many people find weight loss challenging despite their best efforts with diet and exercise. This medication can provide additional support when lifestyle changes alone aren't enough to reach your health goals.

What is Naltrexone and Bupropion?

This medication combines naltrexone, which blocks certain brain receptors, with bupropion, an antidepressant that also affects appetite. Together, they create a powerful team that helps reduce hunger and food cravings while supporting your weight loss efforts.

The combination is specifically designed for weight management in adults who have obesity or are overweight with related health conditions. It's not a quick fix but rather a tool that works alongside healthy eating and regular physical activity.

You might know this medication by its brand name, which your doctor or pharmacist can help you identify. The two active ingredients work better together than either would alone.

What is Naltrexone and Bupropion Used For?

This medication is primarily used to help adults lose weight when they have a body mass index (BMI) of 30 or higher, or a BMI of 27 or higher with weight-related health problems. It's designed for long-term weight management, not short-term weight loss.

Your doctor might recommend this medication if you have weight-related conditions that need attention. These commonly include high blood pressure, type 2 diabetes, or high cholesterol that haven't improved enough with lifestyle changes alone.

The medication can also help if you've struggled with emotional eating or find it difficult to control portion sizes. Many people experience fewer food cravings and feel more satisfied after eating smaller amounts.

In some cases, doctors may prescribe this combination for other conditions, though weight management remains its primary approved use. Your healthcare provider will determine if it's right for your specific situation.

How Does Naltrexone and Bupropion Work?

This medication works by targeting specific areas in your brain that control hunger, satisfaction, and reward feelings from food. It's considered a moderately strong weight management medication that requires careful monitoring.

The bupropion component affects brain chemicals like dopamine and norepinephrine, which influence your mood and appetite. This can help reduce cravings and make you feel less driven to eat when you're not truly hungry.

Naltrexone blocks opioid receptors in your brain, which can reduce the pleasurable feelings you get from eating certain foods. This doesn't eliminate enjoyment from meals but can help break cycles of overeating or emotional eating.

Together, these effects can help you feel satisfied with smaller portions and experience fewer intense food cravings throughout the day. The medication doesn't work instantly and typically takes several weeks to show its full effects.

How Should I Take Naltrexone and Bupropion?

Take this medication exactly as your doctor prescribes, usually twice daily with food to help prevent stomach upset. Starting with food in your stomach can significantly reduce nausea, which is common when beginning this medication.

Your doctor will likely start you on a lower dose and gradually increase it over several weeks. This step-up approach helps your body adjust and reduces the chance of side effects like nausea or dizziness.

Take your morning dose with breakfast and your evening dose with dinner, spacing them about 8 to 12 hours apart. Consistent timing helps maintain steady levels of the medication in your system.

Swallow the tablets whole without crushing, chewing, or breaking them. The extended-release formulation is designed to work slowly throughout the day, and altering the tablets can cause too much medication to be released at once.

If you forget a dose, take it as soon as you remember, but don't take two doses at once. It's better to skip the missed dose if it's almost time for your next scheduled dose.

How Long Should I Take Naltrexone and Bupropion For?

This medication is typically used for long-term weight management, often for several months to years depending on your response and health needs. Your doctor will evaluate your progress every few months to determine if you should continue.

Most people see initial results within 8 to 12 weeks, but the full benefits may take up to 16 weeks to become apparent. If you haven't lost at least 5% of your starting weight after 12 weeks, your doctor may recommend stopping the medication.

The duration of treatment depends on how well the medication works for you and whether you experience any problematic side effects. Some people take it for many months or even years as part of their ongoing weight management strategy.

Your healthcare provider will regularly monitor your progress, blood pressure, and overall health while you're taking this medication. They'll help you decide when it's appropriate to continue, adjust the dose, or consider stopping.

What Are the Side Effects of Naltrexone and Bupropion?

Like all medications, naltrexone and bupropion can cause side effects, though not everyone experiences them. Most side effects are mild to moderate and often improve as your body adjusts to the medication.

The most common side effects you might experience include nausea, constipation, headache, and dizziness. These typically occur during the first few weeks of treatment and often become less bothersome over time.

Common Side Effects

These side effects happen fairly often but are usually manageable and tend to improve with time:

• Nausea and stomach upset
• Constipation
• Headache
• Dizziness
• Trouble sleeping
• Dry mouth
• Diarrhea
• Anxiety or restlessness

Most people find these effects become less noticeable after the first month of treatment. Taking the medication with food can help reduce nausea and stomach problems.

Serious Side Effects

While less common, some side effects require immediate medical attention and shouldn't be ignored:

• Severe mood changes or depression
• Thoughts of self-harm
• Seizures
• Severe allergic reactions
• Rapid or irregular heartbeat
• Severe high blood pressure
• Liver problems (yellowing of skin or eyes)
• Severe kidney problems

Contact your doctor immediately if you experience any of these serious side effects. They can help determine if you should continue the medication or switch to a different treatment.

Rare Side Effects

These side effects occur infrequently but are important to be aware of:

• Severe liver damage
• Angle-closure glaucoma
• Severe allergic reactions with swelling
• Serotonin syndrome (when combined with certain other medications)
• Severe kidney problems
• Heart rhythm problems

While these rare side effects are uncommon, your doctor will monitor you regularly to catch any potential problems early.

Who Should Not Take Naltrexone and Bupropion?

This medication isn't safe for everyone, and your doctor will carefully review your medical history before prescribing it. Certain health conditions and medications can make this combination dangerous or less effective.

People with a history of seizures, eating disorders, or current use of opioid medications should not take this medication. The combination can increase seizure risk and may not work properly if you're taking opioids.

You should also avoid this medication if you have uncontrolled high blood pressure, certain heart conditions, or severe liver or kidney disease. Your doctor will check these conditions before starting treatment.

If you're pregnant, planning to become pregnant, or breastfeeding, this medication is not recommended. The safety during pregnancy hasn't been established, and it can pass into breast milk.

People taking MAO inhibitors or those who have stopped them within the past 14 days should not use this medication due to dangerous drug interactions.

Naltrexone and Bupropion Brand Names

The most common brand name for this combination medication is Contrave, which is widely available in pharmacies across the United States. This is the brand name you'll most likely encounter when your doctor prescribes this medication.

Some insurance plans may cover the brand name while others prefer generic versions when available. Your pharmacist can help you understand your coverage options and find the most cost-effective version.

The generic combination may be available under different names or as separate medications taken together. Your doctor will specify which formulation is best for your situation.

Naltrexone and Bupropion Alternatives

If this medication doesn't work well for you or causes troublesome side effects, several alternatives are available for weight management. Your doctor can help you explore other options that might be better suited to your needs.

Other prescription weight loss medications include orlistat, which blocks fat absorption, and newer medications like semaglutide or liraglutide, which work on different appetite pathways. Each has its own benefits and potential side effects.

Non-medication approaches remain important alternatives, including structured diet programs, behavioral counseling, and in some cases, weight loss surgery. Many people find success with combination approaches that include lifestyle changes plus medical support.

Your healthcare provider can help you understand which alternatives might work best based on your health history, other medications you take, and your weight loss goals.

Is Naltrexone and Bupropion Better Than Phentermine?

Both medications can be effective for weight loss, but they work differently and may be better suited for different people. Phentermine is typically used for shorter periods, while naltrexone and bupropion is designed for longer-term use.

Phentermine mainly suppresses appetite and can cause more stimulant-like side effects such as increased heart rate and blood pressure. Naltrexone and bupropion works on different brain pathways and may be better for people who struggle with emotional eating or food cravings.

The choice between these medications depends on your specific health conditions, other medications you take, and your weight loss goals. People with heart conditions might do better with naltrexone and bupropion, while those needing short-term appetite suppression might prefer phentermine.

Your doctor will consider your complete medical picture to determine which medication is more appropriate for your situation. Some people may try one medication first and switch to another if needed.