Ivacaftor / tezacaftor Side Effects

Medically reviewed by Drugs.com. Last updated on Jun 30, 2021.

Consumer
Professional
FAQ

For the Consumer

Applies to ivacaftor / tezacaftor: oral tablet

Side effects requiring immediate medical attention

Along with its needed effects, ivacaftor / tezacaftor 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 / tezacaftor:

Rare

Nausea
severe constipation
stomach pain
vomiting

Incidence not known

Blindness
blurred vision
dark urine
decreased vision
light-colored stools
loss of appetite
yellow skin or eyes

Side effects not requiring immediate medical attention

Some side effects of ivacaftor / tezacaftor 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

Headache

Less common

Dizziness
stuffy nose

For Healthcare Professionals

Applies to ivacaftor / tezacaftor: oral tablet

General

The most commonly reported side effects have included headache, nasopharyngitis, nausea, sinus congestion, and dizziness.^[Ref]

Nervous system

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

Common (1% to 10%): Dizziness

Ocular

Frequency not reported: Non-congenital lens opacities

Respiratory

Common (1% to 10%): Sinus congestion

Gastrointestinal

Common (1% to 10%): Nausea

Uncommon (0.1% to 1%): Distal intestinal obstruction syndrome

Hepatic

Common (1% to 10%): Transaminase elevations

The incidence of maximum transaminase (ALT or AST) elevations to greater than 8 times the upper limit of normal (8 x ULN), greater than 5 x ULN, or greater than 3 x ULN was similar between drug treated and placebo treated patients (0.2%, 1%, 3.4% versus 0.4%, 1%, 3.4%, respectively). A total of 3 patients in clinical trials permanently discontinued therapy due to elevated transaminases (1 drug treated and 2 on placebo). No drug-treated patient experienced a transaminase elevation greater than 3 x ULN associated with elevated total bilirubin greater than 2 x ULN.