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Oxbryta Side Effects

Generic name: voxelotor

Medically reviewed by Last updated on Feb 13, 2021.

Note: This document contains side effect information about voxelotor. Some of the dosage forms listed on this page may not apply to the brand name Oxbryta.

For the Consumer

Applies to voxelotor: oral tablet

Side effects requiring immediate medical attention

Along with its needed effects, voxelotor (the active ingredient contained in Oxbryta) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking voxelotor:


  • Black, tarry stools
  • chest pain
  • chills
  • cough
  • fever
  • hives or welts, itching or skin rash
  • painful or difficult urination
  • redness of the skin
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • swelling of the face
  • swollen glands
  • trouble breathing
  • unusual bleeding or bruising
  • unusual tiredness or weakness

Side effects not requiring immediate medical attention

Some side effects of voxelotor may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

For Healthcare Professionals

Applies to voxelotor: oral tablet


The more commonly reported adverse reactions have included headache, diarrhea, abdominal pain, nausea, fatigue, rash, and pyrexia[Ref]


Clinical manifestations of serious hypersensitivity reactions may include generalized rash, urticaria, mild shortness of breath, mild facial swelling, and eosinophilia.

Rare (less than 0.1%): Serious hypersensitivity reactions


Very common (10% or more): Diarrhea (20%), abdominal pain (19%), nausea (17%)


Rash includes terms of rash, urticaria, generalized rash, maculo-papular rash, pruritic rash, papular rash, erythematous rash, and vesicular rash.

Very common (10% or more): Rash (14%)


Very common (10% or more): Fatigue (14%), pyrexia (12%)

Nervous system

Very common (10% or more): Headache (26%)


1. "Product Information. Oxbryta (voxelotor)." Global Blood Therapeutics, Inc., South San Francisco, CA.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.