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Ivacaftor Side Effects

In Summary

Commonly reported side effects of ivacaftor include: dizziness. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to ivacaftor: oral granule, oral tablet

Along with its needed effects, ivacaftor 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 ivacaftor:

More common Less common
  • Dark urine
  • fever with or without chills
  • light-colored stools
  • loss of appetite
  • nausea and vomiting
  • stomach pain
  • yellow eyes or skin

Some side effects of ivacaftor 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
  • Blemishes on the skin
  • diarrhea
  • difficulty with moving
  • dizziness
  • muscle aches
  • muscle pain or stiffness
  • pain in the joints
  • pimples
  • rash

For Healthcare Professionals

Applies to ivacaftor: oral granule for reconstitution, oral tablet


Very common (10% or more): Rash (up to 13%)
Common (1% to 10%): Acne[Ref]


Very common (10% or more): Oropharyngeal pain (22%), abdominal pain (16%), diarrhea (13%), nausea (12%)[Ref]


Common (1% to 10%): Increased aspartate aminotransferase, increased hepatic enzymes, transaminase elevations[Ref]

Maximum transaminase (ALT or AST) levels of greater than 8 times upper limit of normal (ULN), greater than 5 times ULN, and greater than 3 times ULN were reported in 2%, 3%, and 6% of patients treated with ivacaftor, respectively.[Ref]


Common (1% to 10%): Increased blood glucose[Ref]


Common (1% to 10%): Arthralgia, musculoskeletal chest pain, myalgia[Ref]

Nervous system

Very common (10% or more): Headache (24%)
Common (1% to 10%): Dizziness, sinus headache[Ref]


Very common (10% or more): Pyrexia (14.7%)
Common (1% to 10%): Bacteria in sputum, ear discomfort, ear pain, tinnitus, tympanic membrane hyperemia, ear congestion[Ref]


Very common (10% or more): Upper respiratory tract infection (22%), nasal congestion (20%), nasopharyngitis (15%), cystic fibrosis lung (38.5%), cough (36.7%), productive cough (12.8%), rales (10%)
Common (1% to 10%): Rhinitis, pharyngeal erythema, pleuritic pain, sinus congestion, wheezing[Ref]


Common (1% to 10%): Breast mass
Uncommon (0.1% to 1%): Breast inflammation, gynecomastia, nipple disorder, nipple pain[Ref]


Postmarketing reports: Non-congenital lens opacities/cataracts (in pediatric patients up to 12 years of age)[Ref]


1. "Product Information. Kalydeco (ivacaftor)." Vertex Pharmaceuticals, Cambridge, MA.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. Cerner Multum, Inc. "Australian Product Information." O 0

Some side effects of ivacaftor may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.