Contrave side effects: A comprehensive guide
Contrave promises weight loss, but for some, the side effects can feel overwhelming. Before you give up, learn how to spot and stop the most troubling reactions.
Key highlights
- Contrave (naltrexone/bupropion) is a weight loss medicine with two active ingredients. It can help you lose weight when used along with a healthy diet and regular exercise.
- Contrave is not a cure for obesity or other health problems. It can help with weight loss when used along with healthy eating, regular exercise, and other lifestyle changes.
- Common side effects of Contrave include nausea, constipation, and headaches. You might also feel dizzy, have trouble sleeping, or get a dry mouth. These side effects often get better as your body gets used to the medicine.
- Serious side effects of Contrave can include high blood pressure, seizures, liver problems, and thoughts of suicide. Get medical help right away if you have any side effects that feel dangerous or life-threatening.
Contrave (naltrexone/bupropion) is a prescription drug approved for weight management in people who are obese or overweight and have at least one health issue related to weight, such as high blood pressure or Type 2 diabetes.
It’s completely normal to feel concerned about side effects when starting a new medication like Contrave. Knowing what to expect can help you feel more in control and less anxious. The good news is that many side effects are mild, temporary, and can be managed with simple lifestyle changes or guidance from your healthcare provider.
Being informed helps you stay safe, stay on track, and get the best results from your treatment. Contrave side effects range from nausea to serious risks. Learn common and rare reactions, how to manage them, and when to seek medical help.
Understanding Contrave and how it works
Contrave (naltrexone hydrochloride/bupropion hydrochloride) is a prescription medicine that combines two active ingredients: bupropion and naltrexone.
Bupropion is often used to treat depression and help people stop smoking, while naltrexone is used to treat alcohol and drug addiction.
Naltrexone belongs to a class of drugs called opioid antagonists, which block opioid receptors in the brain to reduce food cravings and the reward response to eating.
Bupropion belongs to a class of atypical antidepressants and is also used as a smoking cessation aid. It works by affecting brain chemicals like dopamine and norepinephrine, which can help reduce appetite.
Together, these medicines help reduce hunger and control cravings by targetting parts of the brain that regulate appetite. Contrave comes as a long-acting tablet, usually taken twice a day, in the morning and evening.
Contrave’s (naltrexone HCl/bupropion HCl extended-release) mechanism
Contrave helps with weight loss by targeting areas in the brain that control hunger and cravings. It combines two medicines:
Naltrexone blocks brain signals linked to food cravings and affects the “reward center” in the brain that controls pleasurable activities, such as eating.
Bupropion is an antidepressant that can reduce appetite and may help your body burn more energy.
It works on the part of your brain that controls pleasure, like eating, to help reduce food cravings. It may also help you feel less hungry and burn more calories.
Who should choose Contrave?
The FDA has approved Contrave for long-term weight management in adults who meet specific BMI requirements:
- A body mass index (BMI) of 30 kg/m² or higher (obese), or
- A BMI of 27 kg/m² or higher (overweight), plus at least one weight-related medical condition, such as high blood pressure, type 2 diabetes, or high cholesterol (dyslipidemia)
Common side effects of Contrave
Common side effects of Contrave are usually mild and temporary. Many people experience them initially, but they often subside as the body gets used to the medicine.
The most common side effects of Contrave are:
Nausea and vomiting
In clinical trials, nausea and vomiting were some of the most common side effects of Contrave. To help with this, you’ll start on a low dose and slowly increase it over time. The nausea often improves as your body adjusts to the medicine.
To feel better, eat bland foods and avoid fried or spicy meals. Eating smaller meals more often can also help.
If you throw up after taking Contrave, talk to your doctor before taking another dose. Let them know if your nausea is very strong or doesn’t get better. They might change your dose or give you medicine to help with the nausea.
If you experience nausea and vomiting while taking Contrave, here are a few tips:
- Take Contrave with food, preferably small, bland meals.
- Avoid high-fat or spicy foods, which can make nausea worse.
- Sip clear liquids like water, broth, or electrolyte drinks.
- Ginger tea, ginger chews, or ginger supplements may help soothe your stomach.
Contact your doctor if your nausea is severe, doesn’t go away, or comes with other serious symptoms like yellowing of the skin or eyes (jaundice), severe belly pain, or vomiting that doesn’t stop.
Constipation
Constipation is a common side effect of Contrave. Drinking plenty of water and eating foods with lots of fiber can help. Being active and exercising regularly may also improve your symptoms.
If healthy habits aren’t enough, ask your doctor if you can take an over-the-counter medicine for constipation. Let them know if your constipation doesn’t get better or gets worse, as it could lead to other problems like hemorrhoids or a blockage.
Here are some tips on managing constipation:
- Drink more water throughout the day to stay hydrated.
- Slowly add more fiber to your diet with foods like fruits, vegetables, whole grains, and beans.
- Stay active with regular physical activity, like walking or light exercise.
- Talk to your doctor about trying a probiotic supplement, which may help with digestion.
Headache
Contrave can sometimes cause headaches, especially when you first start taking it. This may get better as your body gets used to the medicine.
To help with headaches, drink plenty of water, stay active, get enough sleep, and try to avoid alcohol. If needed, you can take an over-the-counter pain reliever like acetaminophen (Tylenol).
Let your doctor know if your headaches are very painful or don’t go away. There may be another cause, or you might need a different dose of Contrave.
If you are getting headaches while on Contrave, here are some tips you can try:
- Drink plenty of water to stay hydrated.
- Get enough sleep each night.
- Use over-the-counter pain relievers like acetaminophen or ibuprofen (if safe for you).
- Limit or avoid too much caffeine, which can make headaches worse.
Call your doctor if your headache is very painful, doesn’t go away, or comes with other serious symptoms like vision changes or signs of high blood pressure (such as chest pain or dizziness).
Dizziness
Dizziness can happen when you take Contrave, especially in the beginning. It often improves as your body gets used to the medicine, but it’s important to be careful because dizziness can increase your risk of falling or getting hurt.
If you feel dizzy, move slowly and carefully. Be extra careful when driving or doing anything that needs focus or balance until you know how the medicine affects you.
Sometimes dizziness can happen if you’re not eating enough. Make sure to eat healthy, balanced meals. If your appetite is low, try eating smaller meals more often.
If the dizziness is strong or doesn’t go away, talk to your doctor to find out what to do next.
Here are some tips you can try if you feel dizzy while on Contrave:
- Stand up slowly and avoid sudden movements.
- Drink enough water and eat well-balanced meals.
- Be careful when driving or using machines until you know how Contrave affects you.
Talk to your doctor if the dizziness is severe, doesn’t go away, or causes you to fall or feel unsafe.
Insomnia (trouble sleeping)
Contrave can sometimes make it hard to sleep (insomnia), though this isn’t very common. If you’re having trouble sleeping, here are some simple tips that might help:
- Go to bed and wake up at the same time every day.
- Keep your bedroom cool, quiet, and dark.
- Turn off phones, TVs, and other screens before bed.
- Avoid caffeine, nicotine, and alcohol before sleeping.
- Try relaxing activities like reading, calming music, or meditation before bed.
- Exercise regularly during the day.
- Try not to take naps during the day.
If your doctor says it’s okay, you can try an over-the-counter sleep aid or melatonin, but only for a short time. If you still can’t sleep well, talk to your doctor for other options.
Dry mouth
Dry mouth is a possible side effect of Contrave. It might go away on its own, but for some people, it can last longer. It’s important to manage it, as dry mouth can lead to dental problems if not treated.
To help with dry mouth, try sipping water often, chewing sugar-free gum, or using over-the-counter saliva substitutes. Make sure you’re drinking enough fluids every day. Try to avoid caffeine, alcohol, and smoking, as these can make dry mouth worse.
Keep up with regular dental checkups to catch any issues early. If your dry mouth gets worse or becomes too uncomfortable, talk to your doctor about what you can do.
Here are some tips that can help with dry mouth:
- Sip water often throughout the day.
- Chew sugar-free gum to help produce saliva.
- Suck on ice chips or sugar-free hard candies.
- Use over-the-counter saliva substitutes to keep your mouth moist.
Diarrhea
Diarrhea is less common than vomiting with Contrave, but it can still happen in some people.
Here are some tips to help with diarrhea:
- Drink plenty of fluids to stay hydrated.
- Follow a bland diet (like toast, rice, bananas, applesauce).
- Avoid greasy, spicy, or high-fat foods.
Contact your doctor if diarrhea is severe, lasts a long time, or causes signs of dehydration like dry mouth, dizziness, or dark urine.
Hot flashes
Hot flashes are not very common with Contrave, but they can happen in some people. These sudden feelings of heat can be uncomfortable, but there are ways to manage them, such as:
- Dress in layers so you can remove clothing if you feel too warm.
- Avoid triggers like alcohol, caffeine, and spicy foods, which can make hot flashes worse.
- Take cool showers or baths to help lower your body temperature.
- Use a fan or keep your room cool to stay comfortable, especially at night.
If hot flashes become frequent or bothersome, talk to your healthcare professional.
Rare and serious Contrave side effects
Serious side effects from Contrave are rare, but they can happen. If you notice any unusual or severe symptoms, it’s important to get medical help right away.
The most serious side effects of Contrave are:
Suicidal thoughts and behavior
One of the medicines in Contrave is bupropion, which is also used to treat depression. In rare cases, Contrave or other antidepressants have an increased risk of suicidal thoughts or actions, especially in children, teens, or young adults (under the age of 25) during the first few months of treatment or when the dose changes. These thoughts or actions are usually linked to depression or other serious mental health problems.
If you or someone you know is thinking about self-harm, call 911 or contact the Suicide & Crisis Lifeline at 988. Stop taking Contrave and call your doctor right away if you notice:
- New or stronger thoughts about suicide or self-harm
- A suicide attempt
- New or worse feelings of depression, anxiety, agitation, irritability, panic attacks, or changes in mood or behavior
Seizures
Some people who take Contrave have had seizures, especially at high dosages. Seizures can look different for everyone, and some may be hard to notice.
You are more likely to have a seizure if you’ve had one before or if you’re taking other medicines that increase the risk of seizures.
Stop taking Contrave and call your doctor right away if you have any of these signs:
- Muscle twitching, shaking, or movements you can’t control
- Stiff arms or legs
- Feeling very anxious, confused, or suddenly scared
- Feeling dizzy or about to faint
- Passing out or falling down
- Loss of consciousness
Certain factors can raise your risk of having a seizure while taking Contrave. These include a history of seizures, eating disorders like anorexia nervosa or bulimia, suddenly stopping alcohol or sedatives, or taking certain other medications.
To lower your risk of side effects while taking Contrave, it’s important to follow a few simple guidelines. Do not take more than four tablets a day, and be sure to split your dose into two: one in the morning and one in the evening. Start with a low dose and slowly increase it over time, as directed by your doctor. Also, avoid taking Contrave with high-fat meals, because fat can cause your body to absorb too much of the medication, which may increase the chance of side effects.
Increased blood pressure and heart rate
Contrave may raise your blood pressure or make it worse if you already have high blood pressure. It can also make your heart beat faster. Call your doctor if your blood pressure or heart rate goes up while taking this medicine.
If you check your blood pressure and the top number is 180 or more, or the bottom number is 120 or more, get medical attention right away. High blood pressure may not always have clear signs, but watch for these symptoms:
- Sudden and bad headache
- Chest pain
- Dizziness or confusion
- Trouble breathing
- Nausea or vomiting
- Blurry vision or vision changes
- Feeling very anxious
- Ringing in the ears
- Nosebleed
- Skipping or racing heartbeat
Liver damage or hepatitis
Contrave can sometimes cause liver damage. Call your doctor right away if you notice any of these warning signs:
- Feeling sick or throwing up
- Pain in your stomach or belly
- Fever
- Feeling very tired or weak
- Itchy skin
- Not feeling hungry
- Light-colored poop
- Dark-colored pee
- Yellowing of your skin or the whites of your eyes (jaundice)
Severe allergic reactions
Contrave can cause a rare but serious skin reaction called Stevens-Johnson syndrome (SJS), which can be life-threatening. If you get a rash, stop taking Contrave and call your doctor right away. Get emergency help if you have any of these symptoms:
- Painful red or purple skin rash that looks burned or starts to peel
- Blisters or a flat red rash on your skin, mouth, nose, or private areas
- Red, sore, and watery eyes
- Hives
- Severe itching
- Trouble breathing
Angle-closure glaucoma
Contrave can raise pressure inside the eye and may cause or worsen a condition called narrow-angle glaucoma, which can lead to blindness if not treated. Call your doctor right away if you notice any of these warning signs:
- Blurry or lost vision
- Eye pain or redness
- A bad headache or throwing up
- Seeing bright, colorful rings around lights (halos)
Psychiatric and mood changes
Contrave may cause hallucinations or symptoms that seem like a mental health condition. Tell your doctor right away if you notice any of these signs, or if others point them out to you:
- Hearing, seeing, or sensing things that aren’t there
- Believing things that aren’t true, like thinking someone is controlling you
- Having trouble thinking clearly or jumping quickly from one topic to another
- Suddenly not taking care of yourself, like not keeping up with hygiene or work
- Acting in an aggressive or violent way
Contrave is not recommended during pregnancy or while breastfeeding. If you are pregnant, planning to become pregnant, or breastfeeding, it’s important to speak with your doctor about safer treatment options.
Mania (elevated mood)
Contrave can sometimes cause a very high or excited mood, called mania, especially in people with bipolar disorder. This condition includes extreme mood swings, and depression may be the first sign. Taking an antidepressant like Contrave can increase the risk of a manic episode. Call your doctor right away if you notice any of these signs:
- A sudden burst of energy
- Trouble sleeping even when tired
- Fast or racing thoughts
- Risky or reckless behavior
- Feeling overly confident or having big, unusual ideas
- Feeling extremely happy or easily irritated
- Talking much more or faster than normal
How to manage and reduce Contrave side effects
Managing side effects can help you stay on track with your treatment. Here are some simple tips to reduce common side effects from Contrave:
- Take with food: Taking Contrave with a small, bland meal can help lessen nausea.
- Stay hydrated: Drink plenty of water throughout the day to help with side effects like constipation, dizziness, and dry mouth.
- Avoid alcohol: Alcohol can increase the risk of serious side effects such as dizziness, mood changes, or seizures.
- Increase your dose slowly: Follow your doctor’s instructions to gradually raise your dose. This gives your body time to adjust and helps reduce side effects.
If side effects don’t improve or become bothersome, talk to your healthcare provider about adjusting your treatment plan.
Who should not use Contrave?
Contrave is not approved for children and should be avoided in people with certain health conditions. It is not safe for people who have:
- A seizure disorder or a history of seizures
- A history of eating disorders (anorexia or bulimia)
- Opioid dependence or have recently used opioids
- Uncontrolled hypertension (high blood pressure)
- A history of suicidal thoughts or actions
- Are taking monoamine oxidase inhibitors or MAOIs (antidepressants)
- Allergic to its ingredients
If you have any of these conditions, talk to your doctor before starting Contrave, as it could increase the risk of serious side effects.
When to stop taking Contrave
Tell your doctor and discontinue use if you experience any of the following:
- High blood pressure or heart rate
- Do not take it again after a seizure.
- New or worsening suicidal thoughts or behaviors
- Signs of liver damage, like stomach pain, dark urine, or yellow eyes/skin
- Manic episodes (unusually high energy, reckless behavior, fast thoughts)
- Vision problems or eye pain/redness, possible narrow-angle glaucoma
- Severe allergic reactions such as rash, swelling, or trouble breathing
- Opioid use complications: if you require opioids, stop Contrave before use; taking them during Contrave can cause overdose or withdrawal
What should I know before using Contrave?
Only take Contrave if your doctor has prescribed it for you. Follow their instructions and don’t change the dose without talking to them. Keep track of your weight loss and discuss your progress with your doctor.
Don’t share Contrave with anyone else, even if they have similar health issues, as it could be dangerous for them.
Keep Contrave out of reach of children. Swallow the tablets whole. Do not chew, break, or crush them.
If you’re 65 or older, you may have a higher chance of side effects. Talk to your doctor about any risks.
If you’ve been using opioids (prescription or illegal drugs), you must stop before starting Contrave. Taking opioids while on Contrave, or after stopping it, can be very dangerous and may cause you to stop breathing or even lead to death. Do not try to “overcome” Contrave by taking opioids; it could be deadly.
What should I tell my healthcare provider before using Contrave?
Before starting Contrave, tell your doctor about all your health conditions and any other medicines, vitamins, herbs, or supplements you are taking. This helps them decide if Contrave is safe for you.
Be sure to talk about any mental health issues you’ve had. One of the ingredients in Contrave, bupropion, can raise the risk of suicidal thoughts, especially when you first start taking it. Let your doctor know if you have ever had:
- Depression
- Bipolar disorder
- Thoughts of suicide or a past suicide attempt
Also, tell your doctor if you have or have had any of the following:
- Liver or kidney problems
- Diabetes or low blood sugar
- High blood pressure
- Head injury or seizures
- Stroke, heart attack, or other heart problems
- Brain or spine tumors, infections, or blood vessel problems
- Low sodium levels
- Alcohol or drug addiction
Tell your doctor if you are pregnant or planning to become pregnant. Losing weight during pregnancy can harm your baby. Stop taking Contrave if you become pregnant.
Contrave can pass into breast milk. Let your doctor know if you are breastfeeding or plan to. They will help you decide whether to stop breastfeeding or stop taking Contrave.
What should I consider when choosing between Contrave and Wegovy?
When deciding between Contrave and Wegovy (semaglutide), it’s important to consider several key factors:
Administration preference
Wegovy is a shot you give yourself once a week. It comes in a prefilled pen and is injected under the skin, usually in your stomach, thigh, or upper arm. You can do it at home, but if you don’t like needles, Wegovy might not be right for you.
Contrave is a pill you take by mouth. After the first week, you usually take 2 tablets, twice a day. You can take it with or without food, but not with a high-fat meal, as that can make your body absorb too much medicine. The tablets must be swallowed whole; don’t crush or chew them, so if you have trouble swallowing pills, keep that in mind.
Medical history and co-existing medical conditions
Your medical history is a determining factor when choosing between Contrave and Wegovy. Wegovy is generally safer for people with heart disease and is also helpful for those with type 2 diabetes, as it improves blood sugar and reduces heart risks.
Contrave should be avoided if you have a history of seizures, as it can increase seizure risk, or glaucoma, due to potential eye pressure issues. For those with mental health conditions like depression or binge eating, Contrave may help, but it can also cause mood changes, so careful monitoring is needed.
Neither drug is safe during pregnancy or breastfeeding. Always talk to your doctor to choose the best option based on your health.
Side effect profile
When choosing between Wegovy and Contrave, think about which side effects concern you most and how you might handle them.
If you’re worried about stomach issues like nausea, bloating, or diarrhea, know that these are more common with Wegovy, especially in the first few weeks. These side effects often improve over time and can be managed with gradual dose increases, eating bland foods, and staying well-hydrated.
If you’re more concerned about mood changes, insomnia, or anxiety, these are more likely with Contrave, since it affects brain chemicals. It’s important to let your doctor know if you have a history of mental health conditions, so they can monitor you closely or adjust your treatment.
Age
Age matters when choosing a weight-loss medication. Wegovy is approved for both adults and teens aged 12 and older, making it an option for adolescents with obesity. Contrave, however, is approved only for adults 18 and older.
What other drugs can Contrave interact with?
Contrave can interact with several medications and substances, which may increase the risk of side effects or reduce how well the medication works. Always inform your healthcare provider about all medications, supplements, and substances you use.
Below are some key drug interactions to be aware of:
- Opioids (prescription or illicit)
- Monoamine Oxidase Inhibitors (MAOIs)
- Antidepressants and other CNS medications (Benzodiazepines)
- Blood Pressure Medications
- Dopaminergic drugs (levodopa, amantadine)
- Alcohol
FAQs
Does Contrave cause weight gain?
Contrave is used to reduce body weight, not weight gain. However, if it’s not combined with healthy habits or if it’s stopped suddenly, some people might regain weight.
Can Contrave worsen anxiety?
Yes, Contrave can sometimes worsen anxiety in some people. It affects brain chemicals, which may lead to mood changes, nervousness, or anxiety in certain cases.
How long do side effects last?
Side effects from Contrave typically occur in the first few weeks as your body adjusts to the medication. Most side effects go away over time, but if they don’t, you should talk to your doctor.
What if I miss a dose or take too much?
If you miss a dose of Contrave, skip it and take your next dose at the regular time; don’t take two at once. If you take too much, call your doctor or get medical advice right away, as it can be dangerous.
What foods should I avoid with Contrave?
Avoid eating high-fat foods with Contrave because they can make side effects worse. It’s also best to avoid alcohol, as it may increase the risk of serious reactions like seizures or mood changes.
Does Contrave cause hair loss?
Hair loss is not a common side effect of Contrave, but some patients have reported it. If you notice hair thinning while using it, talk to your doctor to check for other possible causes.
Can I drink alcohol while taking Contrave?
It’s best to avoid alcohol while taking Contrave because it can increase the risk of side effects like dizziness, mood changes, or seizures. Drinking alcohol may also make it harder for the medicine to work properly.
How long do Contrave side effects last?
Most Contrave side effects start within the first few days or weeks and often improve as your body adjusts. If side effects last a long time or feel severe, you should talk to your doctor.
Is a generic version available for Contrave?
There is no generic version of the drug available. Contrave is only sold as a brand-name medication.
Tips for success
To get the most benefit from Contrave, it’s important to take a proactive approach. Stay in regular contact with your healthcare provider and share how you’re feeling throughout your treatment.
- Always take Contrave exactly as prescribed, don’t change the dose on your own.
- Be honest with your doctor about your medical history and any other medications or supplements you take.
- Keep a diary of any symptoms or side effects to track how you’re doing.
- Don’t be afraid to ask questions or report any new or worsening symptoms.
- Contrave works best as part of a full weight loss plan that includes healthy eating and regular exercise.
Conclusion
Contrave can be a helpful tool for weight loss when used along with healthy lifestyle changes such as a reduced-calorie diet and regular exercise. However, understanding and managing possible side effects is important for a safe and positive experience.
Common side effects of Contrave include nausea, constipation, and headaches. You might also feel dizzy, have trouble sleeping, or get a dry mouth. These side effects often improve as your body adjusts to the medicine.
Serious side effects of Contrave can include high blood pressure, seizures, and suicidal thoughts. Tell your doctor if you have any side effects that concern you or don’t go away. If you have any side effects that you suspect may be dangerous, get emergency help right away.