What you’ll learn:
- Contrave® combines naltrexone and bupropion to help manage hunger and cravings by targeting specific brain areas.
- Common side effects may include nausea, changes in bowel habits, dizziness, and sleep disturbances, which often improve over time.
- For best results, Contrave® should be used alongside a healthy diet and regular physical activity, and always under medical supervision.
If you’re exploring prescription options to support weight loss, you might have heard of Contrave®. Unlike popular GLP-1 medications like Wegovy® or Zepbound®, Contrave® is a pill—FDA-approved for weight loss in 2014—that combines two existing drugs: bupropion and naltrexone. Bupropion is commonly used to treat depression and help with smoking cessation, while naltrexone is typically prescribed for alcohol or opioid dependence.
Together, this duo works on the brain pathways that regulate hunger, cravings, and reward, helping people make better diet choices, which often leads to weight loss. Contrave® is a unique option for people who struggle with emotional or habitual eating. While it may not be as widely known as GLP-1s, Contrave® has been gaining steady attention as an oral alternative for weight management.
As with any medication, though, it’s important to know what to expect. In this guide, we’ll break down how Contrave® works, explore both common and less common side effects, safety issues, and share practical tips to help you manage them.
How Contrave® affects your body
Contrave® targets two key areas of the brain that play a major role in eating habits: the hypothalamus, which helps regulate hunger, and the mesolimbic reward system, which influences cravings and emotional eating. Its two active ingredients—bupropion and naltrexone—work together to help reduce appetite and food-related urges. Here’s how:
- Bupropion boosts dopamine and norepinephrine, brain chemicals that influence mood, focus, and appetite.
- Naltrexone blocks certain opioid receptors involved in the pleasure and habit-forming response to eating.
By changing how your brain responds to food cues and cravings, Contrave® can help you break patterns like stress eating, boredom snacking, or habitual overeating—common challenges when trying to lose weight.
How it’s taken
Contrave® is a pill taken by mouth, typically twice a day—once in the morning and once in the evening. To minimize side effects, everyone starts with a low dose that gradually increases over several weeks. Your provider will adjust the dose based on how your body responds, aiming to find the right balance between effective weight loss and minimal side effects. The maximum dose is two tablets, twice a day.
What to expect
Because Contrave® changes how your brain processes hunger and reward, side effects are common early on, especially as your body adjusts. The most frequently reported symptoms include nausea, headache, constipation, trouble sleeping, and dizziness. These effects usually ease over time as your brain adapts to the new chemical signals and reduced reward response from food.
When are side effects most likely with Contrave®?
Side effects from Contrave® are most likely to show up during the first few weeks or while your dose is being gradually increased.
Contrave® is prescribed using a gradual, four-week dosing schedule to help minimize side effects. (Each tablet contains 8 mg of naltrexone and 90 mg of bupropion.)
- In Week 1, you’ll take one tablet each morning.
- In Week 2, you’ll take one tablet in the morning and one in the evening.
- In Week 3, the dose increases to two tablets in the morning and one in the evening.
- By Week 4 and onward, you’ll reach the full maintenance dose of two tablets twice daily (a total of 32 mg naltrexone / 360 mg bupropion per day).
The tablets should be swallowed whole and not cut, crushed, or chewed. Contrave® is usually taken with food, but not with high-fat meals, as these can raise drug levels in the system and increase the risk of side effects.
Your healthcare provider will evaluate your progress after 12 weeks; if you haven’t lost at least 5% of your starting weight, they may recommend stopping treatment.
Common side effects of Contrave®
Most side effects are mild to moderate and often improve with time, particularly if your dose is gradually increased as recommended. To help you know what to look for, we’ve broken down the most common side effects as reported on this medication’s clinical trials to give you a clearer picture of how they might show up in everyday life.
Gastrointestinal issues
According to clinical trials, digestive changes are common when you first start Contrave®, as the medication can influence both how your body handles food and how your brain responds to hunger. These symptoms are among the most frequently reported.
| Symptom | Contrave®32 mg/360mg | What can help |
|---|---|---|
| Nausea | 32.5% | Eating slowly, avoiding large meals, and avoiding foods known to cause gas or bloating may help reduce discomfort. If the pain becomes sharp or persistent, contact your provider to rule out more serious causes. |
| Vomiting | 11% | If vomiting occurs, try smaller, more frequent meals and avoid foods that tend to upset your stomach. |
| Diarrhea | 7% | Stay well-hydrated with water or electrolyte-rich fluids to prevent dehydration. Avoid spicy, fatty, or highly processed foods, and stick to bland, gentle meals like rice, bananas, or toast until symptoms improve. |
| Constipation | 19% | Increasing your daily intake of fiber from fruits, vegetables, and whole grains, along with drinking plenty of water, can relieve constipation |
| Abdominal pain | 3% | Eating slowly, avoiding large meals, and steering clear of foods known to cause gas or bloating may help reduce discomfort. If the pain becomes sharp or persistent, reach out to your provider to rule out more serious causes. |
Other symptoms
Because Contrave® works on brain chemistry, it can also cause side effects that aren’t related to digestion. These symptoms often appear during the first few weeks of treatment and usually fade as your body gets more comfortable with the medication.
| Symptom | Contrave®32 mg/360mg | What can help |
|---|---|---|
| Headache | 18% | Stay hydrated, get adequate rest, and try to avoid skipping meals. Over-the-counter pain relievers may be used if approved by your provider. |
| Dizziness | 10% | Staying hydrated and ensuring consistent food intake throughout the day can help minimize dizziness. |
| Insomnia | 9% | Create a calming bedtime routine, avoid screens before bed, and limit caffeine intake after midday to improve sleep quality. |
| Dry mouth | 8% | Drink water consistently throughout the day and consider using sugar-free gum or lozenges to stimulate saliva. A humidifier at night can also help relieve dryness, especially during sleep. |
| Fatigue | 4% | Light physical activity, such as walking or stretching, can help improve alertness and reduce sluggishness. |
| Hot flushes | 4.2% | Wearing lightweight, breathable clothing and staying in a cool environment can reduce discomfort. Drinking cool water and avoiding triggers like spicy foods or alcohol may also help. |
| Sweating | 5% | Stay well-hydrated, and if sweating is excessive or accompanied by other symptoms, let your provider know. |
| Muscle strain | 2% | Staying hydrated and incorporating regular stretching into your routine can reduce muscle spasms. If cramps are painful or frequent, consult your provider to rule out underlying issues. |
In addition to the symptoms listed above, some people taking Contrave® may also experience anxiety (4%) or tremors (4%). If you notice that you’re feeling unusually anxious, restless, or experiencing shaky hands or jitteriness, bring it up with your provider. These symptoms can often be managed with small adjustments to your routine or dosage, and your doctor can help you find the best way to stay on track with your treatment.
Cardiovascular symptoms
Contrave® can also affect your cardiovascular system. These side effects aren’t as commonly reported in clinical trials, but it’s still important to keep them on your radar, especially if you have a history of heart issues or metabolic conditions.
| Symptom | Contrave®32 mg/360mg | What can help |
|---|---|---|
| Palpitations | 2.1% | Avoid caffeine and stimulants, and practice stress-reducing activities like deep breathing or meditation. If palpitations are frequent, persistent, or accompanied by chest pain or dizziness, seek medical attention right away. |
| Hypertension | 6% | Monitor your blood pressure regularly, reduce sodium intake, stay physically active, and maintain a heart-healthy diet. |
| Increased heart rate | 6% | Take note of your pulse and avoid overexertion during activity. Limiting stimulants and managing stress levels can also help. |
Side effects of stopping
Deciding to stop Contrave® is a choice that should be made in partnership with your healthcare provider. They’ll help you taper off to minimize side effects. As you lower your medication, you might notice some changes in how you feel, both physically and emotionally. Here are some common experiences people report during this transition:
- Increased appetite – Without Contrave® helping to regulate hunger cues, you may start feeling hungrier or craving food more frequently than you did while on the medication.
- Weight regain – Some individuals experience a gradual return of weight, especially if lifestyle habits aren’t adjusted to account for the change in appetite and cravings.
- Mood or energy shifts – Because bupropion is part of the Contrave® formula, some people notice subtle changes in mood or energy after discontinuing it, particularly if they are sensitive to its stimulant effects.
Side effects in females
There’s no evidence showing that Contrave® causes different or more severe side effects for females. In clinical studies, the medication appeared to impact men and women similarly, with no female-specific side effects officially documented. That said, individual experiences can still vary, so if you have questions or concerns, or simply want to make sure you’re on the right track, don’t hesitate to talk with your provider. They’re there to support you every step of the way.
Severe side effects and warnings
Most people tolerate Contrave® well and experience mild to moderate side effects, but you’ll need to be aware of the warning signs of some serious conditions. Here are some symptoms and signs of conditions that call for immediate medical attention:
- Seizures: Bupropion, one of the ingredients in Contrave®, lowers the seizure threshold, increasing the risk in those prone to seizures. Symptoms include sudden convulsions, loss of consciousness, stiffening of muscles, or jerking movements.
- Mood changes and suicidal thoughts: Symptoms to watch for include sudden mood swings and changes in behavior.
- Increased blood pressure and heart rate: Symptoms include persistent headaches, chest discomfort, shortness of breath, and a pounding heart.
- Liver toxicity: Rare cases of liver damage have been reported. Be alert for symptoms like jaundice, fatigue, and abdominal pain.
- Severe allergic reactions: Go to the nearest emergency room for any unusual swelling, difficulty breathing, or signs of anaphylaxis.
For a complete list of ingredients and safety details, refer to the Contrave® medication guide.
Boxed warning for Contrave®
Contrave® has a boxed warning due to the increased risk of suicidal thoughts and behaviors. Patients should be monitored for mood changes, especially during the first few months of treatment and during dosage adjustments.
Who shouldn’t take Contrave®
While Contrave® can be an effective option for weight management, it’s not the right fit for everyone. Certain health conditions or medications can increase the risk of side effects or complications, so it’s important to know if you fall into a group where this treatment should be avoided. Always talk to your healthcare provider about your full medical history before starting Contrave®.
You shouldn’t take Contrave® if you:
- Have uncontrolled high blood pressure.
- Have or have had seizures.
- Take other medications containing bupropion.
- Have or have had an eating disorder, such as anorexia or bulimia.
- Are dependent on opioid pain medications, taking medications to help stop opioids, or experiencing opioid withdrawal.
- Drink large amounts of alcohol and abruptly stop.
- Take sedatives, benzodiazepines, or anti-seizure medications and suddenly stop.
- Are taking monoamine oxidase inhibitors (MAOIs), including linezolid.
- Are allergic to naltrexone, bupropion, or any other ingredients in Contrave®.
- Are pregnant or breastfeeding.
Your weight loss journey is unique, and so is your care plan. If you have any of the conditions listed above—or are unsure about how Contrave® might affect you—talk openly with your provider. They’ll help you decide whether it’s the right option and guide you safely through each step, including how to stop if needed.
Comparing the side effects: Contrave® vs. GLP-1 medications
Will you experience more side effects with Contrave® or some other popular medications? Let’s break it down and look at how it differs from popular GLP-1 medications:
| Medication (dose) | Nausea | Vomiting | Diarrhea | Constipation | Dyspepsia | Key differences |
|---|---|---|---|---|---|---|
| Naltrexone and bupropion(Contrave®) | 32.5% | 11% | 7% | 19% | Data not reported | Generally causes less vomiting and diarrhea than GLP-1s, but still has a high incidence of nausea, headache, and mood-related side effects. |
| Semaglutide (2.4 mg) – Wegovy® | 44% | 24% | 30% | 24% | 9% | Higher rates of nausea, vomiting, diarrhea, and constipation than Contrave®. |
| Tirzepatide (15 mg) – Zepbound® | 28% | 13% | 23% | 11% | 10% | Lower nausea and constipation than Contrave®, though vomiting and diarrhea are more commonly reported. |
| Liraglutide (3 mg) – Saxenda® | 39% | 16% | 21% | 19% | 10% | More nausea, vomiting, and diarrhea than Contrave®, with about the same incidence of constipation. |
Your next steps with Contrave® and beyond
Contrave® offers a different path to weight loss—one that focuses on brain chemistry and behavioral patterns rather than hormones or gut-based signals. For people who struggle with emotional eating or constant cravings, this oral medication may provide the extra support needed to create lasting habits. Like any weight loss medication, it works best when paired with a healthy lifestyle, consistent movement, and a focus on sustainable change.
If you’re considering Contrave®, it’s important to weigh the potential benefits and side effects. Everybody responds differently, and what works well for one person might not be the best fit for another. If you have questions, see if you qualify for Noom Med. Our clinicians can decide if medication is right for you and prescribe it if needed. You also get access to all of Noom’s trackers and tools, along with behavioral coaching, to help you navigate everything from medication side effects to emotional eating and lifestyle changes.
