Mavyret's Side Effects: What to Know

Medically Reviewed By Heather Bruce, PharmD
Mavyret has a boxed warning for risk of reactivation of hepatitis B virus (HBV), which is the virus that causes hepatitis B. This is a serious warning from the Food and Drug Administration (FDA). For details, see the “ Mavyret: Side effects explained” section below.

Mavyret: Introduction

Mavyret is a brand-name prescription drug. It’s a type of medication called a direct-acting antiviral drug and contains the following active drugs:

  • glecaprevir, which belongs to a drug class called NS3/4A protease inhibitors
  • pibrentasvir, which belongs to a drug class called NS5A inhibitors

It comes as a tablet and pellet, each of which you swallow.

Mavyret is approved by the Food and Drug Administration (FDA) for use in adults and children ages 3 years and older. It’s prescribed to treat certain types of hepatitis C virus (HCV), which causes hepatitis C. You may take Mavyret for 8 to 16 weeks depending on your specific situation.

Similar to other drugs, Mavyret may cause side effects. Read below for information about possible side effects, including common, mild, and serious ones.

For a general overview of Mavyret, see this article.

If you’d like to take Mavyret, search here to find a healthcare professional who might prescribe it.

Mavyret: More common side effects

Some of Mavyret’s side effects may be more common than others. These side effects may last a few days to weeks. However, some side effects may last longer or become severe or bothersome. Tell your doctor or pharmacist if you have concerns about any side effects with Mavyret.

In Mavyret’s clinical studies, these were some of the side effects that occurred more often:

* For more information about this side effect, see “Mavyret: Side effects explained” below.

Mavyret: Mild side effects

Mavyret can cause mild side effects, which are listed below. However, this list doesn’t include all possible mild side effects. To learn more about Mavyret’s side effects, view the drug’s prescribing information.

Mavyret’s mild side effects include:

The side effects listed above may last a few days to weeks. However, some side effects may last longer or become severe or bothersome. Tell your doctor or pharmacist if you have concerns about side effects with Mavyret.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Mavyret and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Mavyret: Side effects explained” below.

Mavyret: Serious side effects

It’s possible to have serious side effects with Mavyret. Serious side effects are listed below, but this list may not include all possibilities. To learn more about Mavyret’s side effects, view the drug’s prescribing information.

Call your doctor right away if you have serious side effects with Mavyret. However, if you think you’re having a medical emergency or have life threatening side effects, call 911 or your local emergency number.

Serious side effects of Mavyret and their possible symptoms include:

* Mavyret 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 “Mavyret: Side effects explained” section below.
† An allergic reaction is possible after taking Mavyret. However, this side effect was not reported in clinical studies. To learn more, see the “Mavyret: Side effects explained” section below.

Mavyret: Side effects in children

Mavyret is approved to treat hepatitis C in children ages 3 years and older. During the drug’s clinical studies, children experienced side effects that were similar to those in adults. For lists of Mavyret’s side effects, see “Mavyret: Mild side effects” and “Mavyret: Serious side effects” above.

However, certain side effects may be more common in children ages 3 to 11 years than in adults. Examples of these include:

If you have questions about how Mavyret may affect your child, talk with their doctor or a pharmacist.

Mavyret: Common questions about side effects

Here are some common questions about the drug’s side effects and answers to them. Talk with your doctor if you have other questions about this drug.

Will I have side effects after stopping Mavyret treatment?

Possibly. In most cases, side effects should go away after you stop taking Mavyret. However, it takes some time for your body to completely remove the drug from your system. It’s possible you may continue to have some side effects during this time.

A drug’s half-life can be used to estimate how long the drug can stay in your system. A half-life is the amount of time your body takes to remove half a dose of the drug from your body. Typically, it takes four to five half-lives for a single dose to be removed from your system.

Mavyret contains two active drugs: glecaprevir and pibrentasvir. Each one lasts a different amount of time in the body. The half-life of glecaprevir is 6 hours. The half-life of pibrentasvir is 13 hours. So, it may take between 2 to 3 days for Mavyret to clear from your system.

Other factors can affect how long it takes for your body to remove a drug, such as:

  • your age
  • your kidney and liver function
  • other drugs you take
  • your other medical conditions
  • your weight

If you continue to experience side effects after you stop taking Mavyret, talk with your doctor.

Does Mavyret have long-term side effects?

It’s possible. Mild side effects from Mavyret typically occur during treatment with the drug. Depending on your specific situation, your doctor may prescribe Mavyret for 8 to 16 weeks. Usually, side effects go away after your treatment ends.

However, in some cases, severe liver failure can occur while taking Mavyret. In rare cases, this side effect can be fatal. Most cases of severe liver failure were reported in people who had liver disease or moderate or severe liver problems before starting Mavyret. The majority of cases occurred during the first 4 weeks of treatment, but the effects of liver failure may be long term in some people.

Also, if you’ve had hepatitis B in the past, the virus that causes it can reactivate* during Mavyret treatment. (With reactivation, the virus becomes active again and causes symptoms.) Hepatitis B can cause serious liver problems, such as liver failure, which can be life threatening. Be sure to tell your doctor if you’ve had hepatitis B in the past so they can closely monitor you during treatment.

If you are concerned about long-term side effects from Mavyret, talk with your doctor.

* Mavyret 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 “Mavyret: Side effects explained” section below.

Is weight gain a side effect of Mavyret?

It’s not likely that you’ll gain weight during treatment with Mavyret. Weight gain wasn’t a reported side effect in the drug’s clinical studies.

There have been some reports of weight gain in people after they completed hepatitis C treatment with direct-acting antivirals. (Mavyret is a direct-acting antiviral that treats hepatitis C.)

The exact reason for the weight gain after treatment ended is unclear. However, certain factors may increase the risk of weight gain after treatment, such as:

  • your pretreatment weight
  • your age
  • your alcohol intake, if any
  • whether you have cirrhosis (liver scarring)
  • your sustained virologic response (SVR)*

Some people experience weight loss with hepatitis C. This may be caused by loss of appetite from condition-related depression, fatigue, impact on quality of life, or reduced liver function. After hepatitis C treatment, weight gain may be due to improved liver function and reduced chronic (long lasting) liver inflammation.

These factors may lead to an increased sense of well-being, more food consumption, and the improved ability of the body to break down fats for energy and storage. All of this could lead to weight gain.

If you have concerns about weight gain during or after your Mavyret treatment, talk with your doctor.

* With SVR, the level of hepatitis C in your body is undetectable for 12 weeks or more after your treatment ends. An undetectable level of the virus means the virus can’t be detected with a blood test.

Can Mavyret cause hair loss?

No, hair loss wasn’t a reported side effect in clinical studies.

However, hair loss may be a symptom of hepatitis C, which Mavyret is used to treat. Your liver helps your body get the nutrients it needs from food. With hepatitis C, your liver is not functioning properly. This may cause hair loss if your body can’t get the necessary nutrients.

If you have concerns about hair loss during Mavyret treatment, talk with your doctor.

Mavyret: Side effects explained

Here’s detailed information about some of Mavyret’s side effects.

Risk of reactivation of hepatitis B virus

Mavyret has a boxed warning regarding the risk of reactivation of hepatitis B virus (HBV), which is the virus that causes hepatitis B. A boxed warning is the strongest warning required by the Food and Drug Administration (FDA). These warnings alert doctors and patients about drug effects that may be dangerous.

If you’ve previously had hepatitis B, Mavyret treatment raises the risk that the HBV can be reactivated (become active again and cause symptoms). HBV can cause serious liver problems, such as liver failure, which can be fatal in some cases.

Symptoms of liver problems may include:

What to do

Tell your doctor if you’ve had hepatitis B. They’ll likely test everyone for this condition before starting Mavyret treatment. And they may treat your hepatitis B if your test is positive. Once you start taking Mavyret, your doctor will closely monitor you for hepatitis B.

If you have any symptoms of liver problems or hepatitis while taking Mavyret, tell your doctor right away.

Itching

Itching is a common side effect of Mavyret. Also, itching may sometimes be associated with a rash.

In clinical studies, people who had received a liver or kidney transplant were more likely to experience itching as a side effect. Itching was also more likely to occur in people with severe kidney or liver problems.

Hepatitis C and hepatitis B can cause itching as a symptom. With these conditions, you may also have rashes or other itchy skin conditions. Itching can lead to the urge to scratch. Scratching may cause cuts and infections.

Keep in mind that Mavyret is used to treat hepatitis C. If you’ve had hepatitis B before, the hepatitis B virus can be reactivated (become active and cause symptoms) with Mavyret treatment. Mavyret has a boxed warning for this side effect. For more information, see “Risk of reactivation of hepatitis B virus” above.

What to do

If you have bothersome itching while taking Mavyret, talk with your doctor. They can check to determine the cause of your itching. Your doctor may also recommend wearing loose clothing made of cotton, taking cool showers or baths, and avoiding scratching. Some other tips to relieve itching include applying cool compresses or calamine lotion to the areas that itch.

If you have difficulty breathing or swelling of your tongue or face along with your itching, call 911 or your local emergency number right away. These are possible signs of an allergic reaction. (See “Allergic reaction” below for more details.)

Diarrhea

In clinical studies, diarrhea was a common side effect of Mavyret. Loose, frequent stools are a symptom of diarrhea. You may also experience abdominal pain, cramping, and nausea. With diarrhea, you may feel an urgent need to have a bowel movement several times daily.

If you have severe diarrhea, you can lose fluids too quickly and become dehydrated.

What to do

If your diarrhea is bothersome or severe, talk with your doctor. For mild diarrhea, they may recommend the following tips to help with symptom relief:

  • drinking plenty of water
  • avoiding spicy or acidic foods
  • avoiding foods that cause gas
  • avoiding fatty foods
  • eating foods low in fiber but higher in starch, such as white rice or certain hot cereals

Talk with your doctor before taking over-the-counter (OTC) medications for diarrhea. Some OTC medications for diarrhea, such as loperamide (Imodium), may interact with Mavyret. Ask your doctor if there is a safe amount to use together with Mavyret. They can recommend safe ways to manage your diarrhea during treatment.

Fatigue

In Mavyret’s clinical studies, fatigue was one of the most common side effects. The extreme tiredness of fatigue doesn’t go away with sleep.

Fatigue is also a common symptom of chronic (long lasting) hepatitis C, which the drug is used to treat. The cause of hepatitis C-related fatigue is not completely understood. A 2006 study suggests fatigue may be a result of liver injury. A 2018 report suggests fatigue in liver disease and hepatitis infection may involve the nervous system.

Fatigue can also be a symptom of depression. And people with hepatitis C may have a higher risk of depression.

What to do

Talk with your doctor if you are experiencing fatigue while taking Mavyret. If your fatigue is mild, your doctor may recommend some tips to manage it during Mavyret treatment. They might suggest:

  • avoiding daytime naps
  • having a regular sleep schedule
  • avoiding high starch foods and refined sugars
  • drinking plenty of water daily
  • incorporating non-strenuous exercise, such as yoga or walking, into your routine

It also may help to plan your activities ahead of time or ask for help from friends and family, so you don’t overexert yourself.

Headache

In clinical studies, headache was one of the most commonly reported side effects.

Your headaches may be dull and constant or throbbing and sharp. Headache pain can be on one side of your head or all over. You may also have other symptoms with headaches, such as:

  • vision changes
  • eye or neck pain
  • nausea or vomiting
  • sensitivity to light

What to do

If your headaches become bothersome, talk with your doctor. If you have mild headaches, you can help manage them at home. Some things you might try include:

  • taking a warm bath
  • applying a cold compress to your forehead
  • getting enough sleep
  • using relaxation techniques to reduce stress
  • drinking chamomile, peppermint, or lavender tea for calming and hydrating effects

Before using over-the-counter pain relief medications, talk with your doctor. Some of these medications contain acetaminophen (Tylenol), which can harm your liver. Your doctor can recommend safe medications or methods to manage your headaches during Mavyret treatment.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Mavyret. A more severe allergic reaction is rare but possible.

Possible symptoms of mild and serious allergic reactions are listed in the table below.

Mild allergic reaction symptoms Serious allergic reaction symptoms
• itching trouble breathing
rash • swelling in your throat or mouth
flushing • swelling under your skin, possibly in your hands, feet, lips, or eyelids

If you have an allergic reaction to Mavyret, call your doctor right away. This is important to do because the reaction could become severe.

However, if you’re having a medical emergency or your symptoms feel life threatening, call 911 or a local emergency number.

Mavyret: Precautions

The Food and Drug Administration has placed a boxed warning on Mavyret to warn of a possible dangerous side effect. This and other precautions are described below.

Boxed warning: Risk of reactivation of hepatitis B virus

This drug has a boxed warning for the risk of reactivation of hepatitis B virus (HBV), which is the virus that causes hepatitis B. This is a serious warning from the Food and Drug Administration (FDA). For details, see the “Mavyret: Side effects explained” section above.

Other precautions

Be sure to talk with your doctor about your health history before taking Mavyret. This drug may not be the right treatment option if you have certain medical conditions or other factors that affect your health.

The conditions and factors to consider include those described below.

Liver disease. Mavyret can worsen liver disease if you have moderate to severe liver disease before starting the drug. The risk for severe liver failure that can lead to death increases with Mavyret use. If you have a history of liver disease, tell your doctor before starting Mavyret.

Allergic reaction. If you’ve had an allergic reaction to Mavyret or any of its ingredients, your doctor will likely not prescribe it. Ask your doctor what other medications may be better options for you.

Atazanavir or rifampin use. Your levels of a certain liver enzyme (type of protein) can increase if you take Mavyret and atazanavir (Reyataz) together. Using Mavyret and rifampin (Rifadin) together can decrease the effectiveness of Mavyret by reducing the drug level in your body. Taking these drugs could prevent your doctor from prescribing Mavyret due to the risk of harm.

Consuming alcohol during Mavyret treatment

Mavyret isn’t known to interact with alcohol.

However, drinking alcohol can make chronic (long lasting) hepatitis C worse. Cirrhosis (liver scarring) can occur from worsening hepatitis C. Keep in mind that Mavyret is used to treat hepatitis C.

If you are interested in drinking alcohol while taking Mavyret, talk with your doctor. They can tell you how much, if any, is safe for you to drink.

Pregnancy and breastfeeding during Mavyret treatment

It is unknown if Mavyret is safe to use during pregnancy or breastfeeding.

If you are pregnant, breastfeeding, or planning to do either, talk with your doctor. They can discuss the risks of taking Mavyret while pregnant or breastfeeding. Your doctor can also recommend healthy ways to feed your child while taking Mavyret.

Mavyret: What to discuss with your doctor

Mavyret’s common side effects are mild. But serious side effects can occur. Talk with your doctor or pharmacist for additional information about Mavyret. If you have questions about the drug’s side effects, your pharmacist or healthcare professional can help answer them.

In addition to discussing Mavyret with your doctor, you may find the following articles helpful in learning more.

  • Overview of Mavyret. To read an overview of Mavyret, see this article.
  • Drug comparison. To learn how Mavyret compares with Harvoni, read this article.
  • Details about hepatitis C. To learn more about HCV, which Mavyret is used to treat, see this article.

Disclaimer: Healthgrades 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.

Medical Reviewer: Heather Bruce, PharmD
Last Review Date: 2022 Jun 5
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.