Rexulti (brexpiprazole) is a prescription drug that’s used to treat depression and other conditions related to mental health. Rexulti can cause side effects that range from mild to serious. Examples include weight gain and headache.

Rexulti is taken to treat the following conditions:

The active ingredient in Rexulti is brexpiprazole. (An active ingredient is what makes a drug work.) The drug comes as tablets that you swallow.

Keep reading to learn about the common, mild, and serious side effects that Rexulti can cause. For a general overview of the drug, including details about its uses, see this article.

Some people may experience mild or serious side effects during their Rexulti treatment. The most commonly reported side effects in studies of Rexulti were:

  • weight gain*
  • akathisia (feeling of restlessness, such as a constant, uncontrollable urge to move around)

* To learn more about this side effect, see the “Side effects explained” section below.

Rexulti can cause mild side effects in some people. Examples of mild side effects that have been reported with Rexulti include:

* To learn more about this side effect, see the “Side effects explained” section below.

In most cases, these side effects should be temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. Don’t stop taking Rexulti unless your doctor recommends it.

Rexulti may cause mild side effects other than the ones listed above. See the Rexulti prescribing information.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Rexulti, visit MedWatch.

Serious side effects are possible with Rexulti, but they’re less common. Some serious side effects that have been reported with Rexulti include:

If you develop serious side effects while taking Rexulti, call your doctor right away. If the side effects seem life threatening or if you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* Rexulti has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.
† To learn more about this side effect, see the “Side effects explained” section below.
‡ An allergic reaction is possible after taking Rexulti. However, it’s not clear whether this side effect occurred in studies.

Learn more about some of the side effects Rexulti may cause.

Weight gain

Weight gain is possible with Rexulti treatment. In both short-term and long-term studies, this was one of the most common side effects reported in people taking Rexulti.

The amount of weight you might gain with Rexulti can vary. It depends on several factors, including your condition, dosage, other medical conditions, and lifestyle.

What might help

During your Rexulti treatment, your doctor will monitor your weight regularly.

There are things you can do to help prevent or reverse weight gain while you’re taking Rexulti. Some examples include:

  • Choose a balanced diet. If you don’t already, now may be a good time to start monitoring your nutrition. Consider using a calorie-tracking app or journal to track what you’re eating. Keeping track of your foods and portion sizes can help you eat a balanced diet.
  • Talk with a professional. Ask your doctor if they can refer you to a registered dietitian or certified nutritionist. They can provide personalized advice for your specific needs and health goals.
  • Exercise regularly. Consistent physical exercise can help you burn calories and feel good. Talk with your doctor about how you can get started. They can suggest an exercise program that’s safe for your abilities and can help you reach or maintain a healthy weight.

If you have questions or concerns about weight gain with Rexulti, talk with your doctor.

Risk of death in certain older adults

Rexulti treatment may increase the risk for stroke in older adults (ages 65 years and older) who have psychosis that’s related to dementia (memory loss). (With psychosis, you lose touch with reality and hear or see things that aren’t really there.) Rexulti may also increase the risk of death in people who have Alzheimer’s disease with psychosis that’s related to dementia and doesn’t involve agitation.

Rexulti has a boxed warning for this side effect. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It alerts doctors and patients about a drug’s effects that may be dangerous.

For this reason, Rexulti treatment isn’t recommended for adults ages 65 and older with this condition. In addition, the drug isn’t recommended for people who have Alzheimer’s disease with psychosis that’s related to dementia and doesn’t involve agitation.

What might help

If you’re age 65 or older and have a history of dementia and psychosis, you shouldn’t take Rexulti. Instead, talk with your doctor about other treatment options.

If you have Alzheimer’s disease with psychosis that’s related to dementia and doesn’t involve agitation, you also shouldn’t take Rexulti. You can talk with your doctor to learn about other treatment options.

Risk of suicidal thoughts and behaviors in young adults

Rexulti may raise the risk of suicidal thoughts and behaviors in people ages 24 years or younger. In fact, Rexulti has a boxed warning for this risk. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It alerts doctors and patients about a drug’s effects that may be dangerous.

If you’re in this age range and are taking Rexulti, your doctor will monitor you closely during your treatment. This is especially important when you first start taking the drug and after any dose increases.

Note: Rexulti may be prescribed to certain children ages 13 and older who have schizophrenia. Your child should only take this drug if their doctor prescribes it.

What might help

If you feel comfortable, consider telling your family or other household members that you’re starting Rexulti. You can explain that this medication is known to raise the risk of suicidal thoughts or behaviors. This way, the people around you can check in with you to see how you’re feeling. They may notice changes in your behavior before you notice them and can encourage you to get help.

If you have thoughts of harming yourself, get medical attention right away. If this occurs, your doctor may recommend that you stop taking Rexulti.

Suicide prevention

If you think someone is at immediate risk of self-harm or hurting another person:

  • Call 911 or your local emergency number.
  • Stay with the person until help arrives.
  • Remove any guns, knives, medications, or other things that may cause harm.
  • Listen, but don’t judge, argue, threaten, or yell.

If you or someone you know is considering suicide, get help from a crisis or suicide prevention hotline. Try the National Suicide Prevention Lifeline at 800-273-8255

Headache

Some people have experienced headaches during their Rexulti treatment. In most cases, this side effect usually goes away after a few weeks, once your body adjusts to the drug.

What might help

If you’re looking for medication to relieve headaches from Rexulti, an over-the-counter (OTC) pain reliever may help. Some OTC options include aspirin, acetaminophen (Tylenol), or ibuprofen (Advil, Motrin). If you’re not sure which OTC pain reliever is safe for you, talk with your doctor or pharmacist.

Other remedies can also be used to ease headaches. Consider the following tips, which can be used with or without OTC pain relievers.

  • Stay hydrated. Headaches can occur or get worse if you don’t drink enough fluids. Try to drink plenty of fluids throughout the day.
  • Heat therapy. Taking a hot shower or bath or using a heating pad can help relax tense muscles and provide some relief.
  • Exercise. Go for a walk or do another form of exercise. Light to moderate exercise can help release endorphins (brain chemicals) and may help ease your headache pain.
  • Limit screen time. Spending too much time looking at screens can cause or worsen headaches. Consider taking regular screen breaks with the 20-20-20 rule: Every 20 minutes, take a 20-second break to look at something 20 feet away.

If your headaches aren’t relieved with these suggestions or if they become severe, talk with your doctor. They may suggest other ways to relieve headaches from Rexulti.

Insomnia or abnormal dreams

Rexulti may cause insomnia (trouble sleeping) or abnormal dreams in some people.

In studies of Rexulti, insomnia was reported as a common side effect. Abnormal or unusual dreams have also been reported with Rexulti use, but not during studies.

What might help

Insomnia from Rexulti may get better or go away on its own after a few weeks or months. If you’re looking for ways to overcome trouble sleeping while taking Rexulti, here are a few suggestions:

  • Practice good sleep hygiene. Adding certain steps to your routine can help your body prepare for sleep.
  • Avoid caffeine later in the day. For most people, consuming caffeine within 3 to 7 hours of bedtime can cause trouble sleeping.
  • Try an over-the-counter (OTC) sleep aid. Some examples include diphenhydramine (Benadryl, ZzzQuil) and doxylamine (Unisom SleepTabs). If you’re not sure which OTC sleep aid is safe for you, check with your doctor or pharmacist.
  • Consider natural remedies. For some people, it can be helpful to drink chamomile tea or take a melatonin supplement before bedtime. If you’re not sure whether natural remedies are safe for you, talk with your doctor or pharmacist.

If you’re concerned about insomnia or abnormal dreams with Rexulti, talk with your doctor. They may suggest ways to relieve this side effect or recommend changes to your treatment plan.

Allergic reaction

Like most drugs, Rexulti can cause an allergic reaction in some people. But it’s not clear if or how often allergic reactions to Rexulti occurred in studies.

Symptoms can be mild or serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • facial swelling
  • hives
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest an over-the-counter oral antihistamine, such as diphenhydramine (Benadryl), or a topical product, such as hydrocortisone cream, to manage your symptoms.

If your doctor confirms you had a mild allergic reaction to Rexulti, they’ll decide whether you should continue taking it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you had a serious allergic reaction to Rexulti, they may have you switch to a different treatment.

Keeping track of side effects

During your Rexulti treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of drug you were taking when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help your doctor learn more about how a drug affects you. And your doctor can use this information to adjust your treatment plan if needed.

Learn answers to some frequently asked questions about Rexulti’s side effects.

Do side effects from Rexulti vary by tablet strength (0.25 mg, 0.5 mg, 1 mg, 2 mg, 3 mg, 4 mg)?

Yes, the risk of developing certain side effects may be greater with higher strengths of Rexulti. In studies of Rexulti, restlessness and akathisia were reported more often in people taking higher strengths than in those taking lower strengths. (With akathisia, you have feelings of restlessness, such as a constant, uncontrollable urge to move around.)

But not all side effects of Rexulti vary by tablet strength. For more details on how often side effects occurred in studies, see Rexulti’s prescribing information.

Will Rexulti make me tired?

It’s possible that Rexulti may make you feel tired. In studies, fatigue (lack of energy) and drowsiness were reported by people taking Rexulti to treat depression.

Keep in mind that for depression, Rexulti is prescribed along with antidepressant medication. Tiredness is a side effect of antidepressants as well.

Tiredness was also reported as a side effect in studies of people taking Rexulti for schizophrenia, but it was less common.

Side effects related to being tired may improve after a few weeks or months of taking Rexulti once your body gets used to the drug. To be safe, you shouldn’t drive or operate heavy machinery when you start taking Rexulti until you see how it makes you feel.

If tiredness from Rexulti doesn’t go away or becomes severe, talk with your doctor.

Can Rexulti cause withdrawal symptoms if I stop my treatment?

It’s possible. There haven’t been specific reports of withdrawal symptoms when Rexulti was stopped. But withdrawal symptoms have been reported with medications that are similar to Rexulti.

Rexulti belongs to a group of drugs called antipsychotics. Research has shown that withdrawal symptoms may occur weeks after antipsychotic drugs are stopped. Withdrawal symptoms could be more severe if Rexulti is stopped suddenly. You could also notice a return or worsening of your depression or schizophrenia symptoms.

Withdrawal symptoms may include:

If you’re interested in stopping your Rexulti treatment, talk with your doctor first. If they agree that you should stop taking Rexulti, they’ll likely have you slowly decrease your dose over time. This can help prevent withdrawal symptoms. Your doctor may also suggest another treatment to replace Rexulti.

How long do side effects from Rexulti last?

How long you experience side effects from Rexulti can vary. Some side effects may be temporary, while others can be long term.

For most people, the following side effects improve or go away within a few weeks or months:

  • headache
  • indigestion (upset stomach)
  • constipation
  • diarrhea
  • tiredness

Other side effects may last for as long as you take Rexulti. These include akathisia and weight gain.

Some side effects of Rexulti don’t go away on their own. These include hyperglycemia (high blood sugar) and high levels of cholesterol or triglycerides. To treat these side effects, your doctor may recommend long-term management with medication, diet, and exercise, even after you stop taking Rexulti.

If you’re concerned about how long side effects last from Rexulti, talk with your doctor or pharmacist.

This drug comes with several warnings.

Boxed warnings

Rexulti has two boxed warnings. Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA). The boxed warnings for Rexulti include:

  • Increased risk of death in certain older adults. Rexulti should not be taken by adults ages 65 years or older who have psychosis that’s related to dementia. This is because Rexulti can raise the risk for stroke and death in certain older adults with this condition. Rexulti should also not be taken by people who have Alzheimer’s disease with psychosis that’s related to dementia and doesn’t involve agitation.
  • Risk of suicidal thoughts and behaviors in young adults. Rexulti may raise the risk of suicidal thoughts and behaviors in people ages 24 years or younger. If you’re in this age range and are taking Rexulti, your doctor will monitor you closely during your treatment. This is especially important when you first start taking the drug and after any dose increases. If you have thoughts of harming yourself, get medical attention right away.

To learn more about these boxed warnings, see the “Side effects explained” section above.

Other warnings

Rexulti may not be right for you if you have certain medical conditions or other factors that affect your health. If you think you’ve had or have any of the factors listed below, talk with your doctor. Be sure to tell them all about your health history before starting Rexulti. They’ll decide whether Rexulti is safe for you and recommend any important monitoring.

Diabetes. Rexulti can cause changes in your metabolism that lead to hyperglycemia (high blood sugar). If you already have high blood sugar or diabetes, taking Rexulti may make your condition worse. Very high blood sugar levels can cause serious harm, including diabetic ketoacidosis, diabetic coma, and in rare cases, death. If you have diabetes, talk with your doctor about how to manage your blood sugar levels while you’re taking Rexulti. This may include checking your blood sugar, taking medications, and changing your diet or activity level.

High cholesterol. Rexulti can cause changes in your metabolism. This can lead to high levels of cholesterol or triglycerides. If you already have high cholesterol or triglyceride levels, taking Rexulti can make your condition worse. Before starting Rexulti, talk with your doctor about a plan for managing your cholesterol and triglycerides. This plan may include the use of medications and changing your diet or activity level.

Seizures. Rexulti may raise your risk for seizures, especially if you’ve had seizures in the past. If you’ve had seizures before, talk with your doctor before starting Rexulti.

Heart or blood pressure problems. If you’ve had heart or blood pressure problems, talk with your doctor before taking Rexulti. This is because Rexulti may cause orthostatic hypotension. For some people with certain heart rhythm or blood pressure problems, orthostatic hypotension could worsen your condition.

Liver or kidney damage. If you have liver or kidney problems or have had them in the past, be sure to tell your doctor before taking Rexulti. They may want to test your blood to check the health of your liver or kidneys. They may also prescribe a lower dose of Rexulti for you.

Poor metabolizers of certain drugs. Because of genetics, some people’s bodies are poor metabolizers of certain drugs. This means their bodies can’t break down certain drugs as well as they should. This may lead to potentially dangerous side effects. Talk with your doctor to find out if your body is a poor metabolizer of certain drugs. If so, your doctor may prescribe a lower dose of Rexulti that’s safe for you to take.

History of compulsive behaviors. Rexulti may raise your risk for compulsive behaviors, such as gambling, binge eating, or sexual urges. If you have a history of gambling problems or other addictions, talk with your doctor. They may suggest a plan for monitoring for these behaviors during your Rexulti treatment, or they may recommend other treatment options.

Allergic reaction. If you’ve had an allergic reaction to Rexulti or any of its ingredients, you shouldn’t take Rexulti. Ask your doctor what other medications are better options for you.

Alcohol and Rexulti

It isn’t known whether it’s safe to drink alcohol while taking Rexulti. But alcohol could worsen some side effects of this drug, such as tiredness.

Also, consuming excessive amounts of alcohol can cause liver damage. This can raise your risk for side effects from Rexulti.

It’s also important to note that alcohol use can possibly worsen your depression or schizophrenia.

If you drink alcohol and you have questions about consuming it with Rexulti, talk with your doctor. They can let you know how much alcohol, if any, is safe to drink with your condition and treatment plan.

Pregnancy and breastfeeding while taking Rexulti

Below are details about taking Rexulti during pregnancy or while breastfeeding.

Pregnancy

It’s not known whether Rexulti is safe to take while pregnant. The drug hasn’t been tested during pregnancy.

But extrapyramidal symptoms (uncontrolled movements) and withdrawal symptoms have occurred in newborns whose birth mothers took a drug similar to Rexulti during the third trimester of pregnancy. (Withdrawal symptoms are side effects that can occur when you stop taking a drug your body has become used to.) These withdrawal symptoms were reported after the drugs were released onto the market.

Withdrawal symptoms reported in these newborns ranged from mild to severe. They included:

If you’re pregnant or planning to become pregnant, talk with your doctor before starting Rexulti treatment.

You and your doctor may decide that you should use Rexulti during pregnancy. If so, consider joining the National Pregnancy Registry for Atypical Antipsychotics. (Rexulti is an atypical antipsychotic.) You can join by calling 866-961-2388 or visiting the registry website.

Breastfeeding

It’s not known whether Rexulti is safe to take while breastfeeding, as this use of the drug hasn’t been studied.

If you’re breastfeeding or planning to breastfeed, talk with your doctor before starting Rexulti treatment. They’ll discuss the best options for you and your child during this time.

Rexulti can be an effective treatment option for major depressive disorder (MDD) and schizophrenia. But for some people, this drug can cause mild or serious side effects.

When you’re considering a new medication, it’s important to talk with your doctor about your risk for side effects. They’ll help you decide whether the potential benefits of Rexulti for your condition outweigh its risks.

Here are some suggestions to get the conversation started with your doctor:

  • With my current health conditions, is it safe for me to take Rexulti?
  • Do my other medications raise my risk for side effects with Rexulti?
  • Will I need to get blood tests to check for Rexulti’s side effects?

To learn more about Rexulti, see these articles:

To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

Q:

I’ve heard that weight gain is common with Rexulti. Why does the drug cause weight gain?

Anonymous

A:

Rexulti can affect your body’s metabolism (chemical processes in your body). In studies, people taking Rexulti for either depression or schizophrenia were more likely to gain weight compared with those using a placebo. (A placebo is a treatment with no active drug.)

In addition, people taking Rexulti for depression in studies also experienced increased appetite, which can lead to weight gain.

Your doctor will monitor your weight before and during your Rexulti treatment. If you have concerns about weight gain with this drug, talk with your doctor.

The Healthline Pharmacist TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.