Oxbryta (voxelotor) is a brand-name drug that’s prescribed for sickle cell disease in adults and certain children. As with other drugs, Oxbryta can cause side effects, such as headache, abdominal pain, and diarrhea.

Oxbryta can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Oxbryta in clinical trials:

  • abdominal pain
  • nausea
  • skin rash
  • diarrhea*
  • headache*

* For more information about this side effect, see “Side effect specifics.”

Mild side effects can occur with Oxbryta use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Oxbryta’s prescribing information.

Mild side effects that have been reported with Oxbryta include:

  • fever
  • abdominal pain
  • nausea
  • skin rash
  • diarrhea*
  • headache*

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

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

* For more information about this side effect, see “Side effect specifics.”

Oxbryta may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Oxbryta’s prescribing information.

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

Serious side effects that have been reported and their symptoms include:

  • pulmonary embolism (blood clot in the lung), which may include symptoms such as:
    • chest pain
    • cough, including coughing up blood
    • shortness of breath
    • trouble breathing
  • severe skin reactions, which can be fatal and may include symptoms such as:
  • severe headache*
ALLERGIC REACTION

For some people, Oxbryta can cause an allergic reaction. In general, symptoms of allergic reaction can be mild or serious.

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to Oxbryta, your doctor may recommend taking a different medication instead.

Oxbryta may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

How do the side effects of Oxbryta and hydroxyurea (Hydrea) compare?

Some of the more common side effects of hydroxyurea (Hydrea) are similar to Oxybryta’s mild side effects. These include digestive side effects, such as nausea, diarrhea, and abdominal pain. However, hydroxyurea and Oxbryta belong to different drug classes, so they have some side effects that differ.

Hydroxyurea can affect your immune system, making it weaker than usual. Because of this, hydroxyurea has a boxed warning for the risk of low blood cell counts. This can lead to infections and an increased risk of certain cancers. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). Oxbryta doesn’t have any boxed warnings, but it may cause serious side effects in some cases. (For details, see the “Serious side effects of Oxbryta” section.)

You can learn more about how these two drugs compare by talking with your doctor or pharmacist.

Does Oxbryta cause long-term side effects?

No, Oxbryta isn’t likely to cause long-term side effects. In clinical trials, there weren’t any specific reports of side effects that happened after taking the drug for a long time. There also weren’t reports of side effects that lasted after the drug was stopped.

That said, if you experience side effects that aren’t going away or that develop after taking Oxbryta for a long time, tell your doctor. They can determine the most likely cause and suggest ways to manage them.

Learn more about some of the side effects that Oxbryta may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Oxbryta.

Headache

Headache was the most common side effect reported in clinical trials of Oxbryta. It was also a common reason that people had to stop taking the drug or needed a lower dosage of Oxbryta. In some cases, the headache was severe.

What you can do

If you develop headaches while taking Oxbryta, tell your doctor. They can determine the most likely cause and suggest ways to manage it. This may include taking over-the-counter (OTC) pain relievers, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin).

Diarrhea

Diarrhea was also a very common side effect in clinical trials of Oxbryta. Like headache, diarrhea was a common reason for stopping treatment or lowering the dose of Oxbryta.

What you can do

Tell your doctor if you experience diarrhea during Oxbryta treatment. They can determine the most likely cause and suggest ways to manage it. This may include taking it with food to reduce digestive upset or taking an OTC remedy.

Below is important information you should consider before taking Oxbryta.

Other precautions

Before taking Oxbryta, discuss your health history with your doctor. Oxbryta may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

  • liver disease
  • previous allergic reaction to this or a similar drug
  • pregnancy
  • breastfeeding
  • alcohol consumption

Disclaimer: Medical News Today 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.