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Burosumab Side Effects

For the Consumer

Applies to burosumab: subcutaneous solution

Along with its needed effects, burosumab 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 or nurse immediately if any of the following side effects occur while taking burosumab:

More Common

  • Bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • bone malformations
  • confusion
  • difficulty in breathing
  • fast heartbeat
  • fever
  • frequent bone fractures
  • hives, itching, skin rash
  • hoarseness
  • irregular heartbeat
  • irritation
  • joint pain, stiffness, or swelling
  • mood or mental changes
  • muscle cramps in the hands, arms, feet, legs, or face
  • numbness and tingling around the mouth, fingertips, or feet
  • pain in the arm or leg
  • redness of the skin
  • seizures
  • slowed growth
  • stomach cramps
  • swelling of the eyelids, face, lips, hands, or feet
  • tightness in the chest
  • tremor
  • troubled breathing or swallowing

Some side effects of burosumab 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 burosumab: subcutaneous solution


The most commonly reported adverse reactions in pediatric patients have included injection site reactions, vomiting, pyrexia, and extremity pain. In adult patients, back pain, tooth infection, restless leg syndrome, dizziness, and constipation have been reported. In both adults and pediatric patients, headache and decreased vitamin D has been reported.[Ref]


Increased blood phosphorus was reported in 6% of adult patients during clinical trials. There were no reports of increased blood phosphorus in pediatric clinical trials.

Very common (10% or more): Vitamin D decreased (up to 37%)

Common (1% to 10%): Blood phosphorus increased


Very common (10% or more): Vomiting (up to 48%), toothache (up to 23%), tooth abscess (up to 23%)

Common (1% to 10%): Constipation


In pediatric patients, the more frequent events that were considered potential hypersensitivity events included rash (22%), injection site rash (6%), and urticaria (5%). In adult patients approximately 6% of patients in both the study group and placebo group experience mild or moderate hypersensitivity reactions that did not require drug discontinuation.

Frequency not reported: Hypersensitivity reactions


Very common (10% or more): Rash (up to 27%)

Rash includes pruritic, maculopapular, and pustular rashes


Spinal stenosis is common in adults with X-linked hypophosphatemia (XLH). In phase 2/3 studies, 6 patients (n=176) underwent spinal surgery for what appeared to involve progression of a preexisting spinal stenosis. It is unknown if therapy exacerbates spinal stenosis or spinal cord compression.

Very common (10% or more): Extremity pain (up to 46%), myalgia (up to 17%), back pain (15%)

Common (1% to 10%): Spinal surgery


Very common (10% or more): Pyrexia (up to 48%)


Injection site reactions have included erythema, pruritus, swelling, pain, rash, bruising, discoloration, discomfort, hematoma, hemorrhage, induration, macule, and urticaria at the injection site

Very common (10% or more): Injection site reaction (up to 67%)

Nervous system

Very common (10% or more): Headache (up to 73%), dizziness (up to 15%), restless leg syndrome (12%)


1. "Product Information. Crysvita (burosumab)." Ultragenyx Pharmaceutical, Novato, 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.