The information contained in this section of the site is intended for US healthcare professionals only.

Are you a US healthcare professional?

You are now leaving You will be redirected to

You are now leaving You will be redirected to

You are now leaving You will be redirected to

Important Safety Information

Do not take SYMDEKO® (tezacaftor/ivacaftor and ivacaftor) if you take certain medicines or herbal supplements such as:

  • antibiotics such as rifampin (Rifamate®, Rifater®) or rifabutin (Mycobutin®)
  • seizure medicines such as phenobarbital, carbamazepine (Tegretol®, Carbatrol®, Equetro®) or phenytoin (Dilantin®, Phenytek®)
  • St. John’s wort

Talk to your doctor before taking SYMDEKO if you take any of the medicines or herbal supplements listed above.

Before taking SYMDEKO, tell your doctor about all of your medical conditions, including if you:

  • have or have had liver problems
  • have kidney problems
  • are pregnant or plan to become pregnant. It is not known if SYMDEKO will harm your unborn baby. You and your doctor should decide if you will take SYMDEKO while you are pregnant
  • are breastfeeding or planning to breastfeed. It is not known if SYMDEKO passes into your breast milk. You and your doctor should decide if you will take SYMDEKO while you are breastfeeding

SYMDEKO may affect the way other medicines work, and other medicines may affect how SYMDEKO works.

Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements, because the dose of SYMDEKO may need to be adjusted when taken with certain medicines.

Especially tell your doctor if you take:
  • antifungal medicines such as ketoconazole (e.g., Nizoral®), itraconazole (e.g., Sporanox®), posaconazole (e.g., Noxafil®), voriconazole (e.g., Vfend®), or fluconazole (e.g., Diflucan®)
  • antibiotics such as telithromycin (e.g., Ketek®), clarithromycin (e.g., Biaxin®), or erythromycin (e.g., Ery-Tab®)

What should I avoid while taking SYMDEKO?

  • SYMDEKO can cause dizziness in some people who take it. Do not drive a car, use machinery, or do anything that needs you to be alert until you know how SYMDEKO affects you.
  • Avoid food or drink that contains grapefruit or Seville oranges while you are taking SYMDEKO.

What are the possible side effects of SYMDEKO?

SYMDEKO can cause serious side effects, including:
  • High liver enzymes in the blood have been reported in people treated with SYMDEKO or treated with ivacaftor alone. Your doctor will do blood tests to check your liver:
    • before you start SYMDEKO
    • every 3 months during your first year of taking SYMDEKO
    • every year while you are taking SYMDEKO

    Your doctor may do blood tests to check the liver more often if you have had high liver enzymes in your blood in the past.

    Call your doctor right away if you have any of the following symptoms of liver problems:
    • pain or discomfort in the upper right stomach (abdominal) area
    • yellowing of your skin or the white part of your eyes
    • loss of appetite
    • nausea or vomiting
    • dark, amber-colored urine

  • Abnormality of the eye lens (cataract) in some children and adolescents treated with SYMDEKO or with ivacaftor alone. If you are a child or adolescent, your doctor should perform eye examinations before and during treatment with SYMDEKO to look for cataracts.

The most common side effects of SYMDEKO include headache, nausea, sinus congestion, and dizziness.

These are not all the possible side effects of SYMDEKO. Call your doctor for medical advice about side effects. You are encouraged to report side effects to FDA at 1-800-FDA-1088.

For further information, please see full Prescribing Information, including Patient Information.

What is SYMDEKO?

SYMDEKO is a prescription medicine used for the treatment of cystic fibrosis (CF) in patients aged 12 years and older who have two copies of the F508del mutation, or who have at least one mutation in the CF gene that is responsive to treatment with SYMDEKO.

Talk to your doctor to learn if you have an indicated CF gene mutation.

It is not known if SYMDEKO is safe and effective in children under 12 years of age.