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URL of this page: https://medlineplus.gov/druginfo/meds/a618022.html

Tezacaftor and Ivacaftor

pronounced as (tez" a kaf' tor) and (eye'' va kaf' tor)

Why is this medication prescribed?

Tezacaftor and ivacaftor is used to treat certain types of cystic fibrosis (CF; an inherited condition that affects the lungs and other parts of the body). Tezacaftor is in a class of medications called cystic fibrosis transmembrane conductance regulator (CFTR) correctors. Ivacaftor is in a class of medications called cystic fibrosis transmembrane conductance regulator (CFTR) potentiators. Both of these medications work by improving the function of a protein in the body to decrease the build-up of thick mucus in the lungs and improve other cystic fibrosis symptoms.

How should this medicine be used?

Tezacaftor and ivacaftor come as tablets to take by mouth. Take with fatty food twice a day, 12 hours apart. Take tezacaftor and ivacaftor at around the same times every day.

Each daily dose is usually given as 2 different tablets that have different ingredients. One tablet (combination of tezacaftor and ivacaftor) is yellow or white and the other table (ivacaftor) is blue. Take tezacaftor and ivacaftor (1 yellow or white tablet) every morning and ivacaftor (1 blue tablet) every evening, 12 hours apart.

Take tezacftor and ivacaftor exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

Take tezacaftor and ivacaftor with fatty foods such as eggs, butter, nuts, peanut butter, cheese pizza, and whole-milk dairy products (such as whole milk, cheese, and yogurt). Talk to your doctor about other fatty foods to eat with these medications.

Tezacaftor and ivacaftor controls cystic fibrosis, but does not cure it. Continue to take these medications even if you feel well. Do not stop taking these medications without talking to your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking the tezacaftor and ivacaftor,

  • tell your doctor or pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
  • you should know that some medications should not be taken with tezacaftor and ivacaftor. Other medications may cause dosing changes or extra monitoring when taken with tezacaftor and ivacaftor. Make sure you have discussed any medications you are currently taking or plan to take before starting tezacaftor and ivacaftor with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking tezacaftor and ivacaftor, please get the advice of your doctor or pharmacist.
  • you should know that the following nonprescription or herbal products may interact with tezacaftor and ivacaftor: St. John's wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking tezacaftor and ivacaftor. Do not start any of these medications while taking the combination of tezacaftor and ivacaftor without discussing with your healthcare provider.
  • tell your doctor if you have or have ever had mental health problems or kidney or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking tezacaftor and ivacaftor, call your doctor.
  • you should know that these medications may make you dizzy. Do not drive a car or operate machinery until you know how these medications affect you.
  • you should know that depression, anxiety, thinking about or committing self harm or suicide, and sleep difficulties have been reported with elexacaftor, tezacaftor, and ivacaftor. Before beginning elexacaftor, tezacaftor, and ivacaftor, tell your doctor if you have or have ever had depression, anxiety, thoughts of harming yourself or attempting suicide in the past, or sleep difficulties. During treatment, call your doctor right away if you start experiencing any of the following: changes in mood, mood swings, difficulties regulating emotion, trouble sleeping, anxious thoughts, or thoughts of harming yourself or others.

What special dietary instructions should I follow?

Do not eat grapefruit or drink grapefruit juice while taking these medications.

What should I do if I forget a dose?

Take the missed dose as soon as you remember if it is within 6 hours of the missed dose. However, if it is more than 6 hours, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Tezacaftor and ivacaftor may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • nasal congestion
  • dizziness
  • nausea

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • yellowing of the skin or eyes, pain in the upper right part of the stomach, loss of appetite, nausea, vomiting, pale stools, or dark urine
  • rash; hives; itching; swelling of the face, eyes, lips, tongue, mouth, or throat; wheezing; difficulty breathing or swallowing; or lightheadedness or dizziness

Tezacaftor and ivacaftor may cause cataracts (clouding of the lens of the eye that may cause vision problems) in children and teenagers. Children and teenagers taking tezacaftor and ivacaftor should see an eye doctor before and during their treatment. Talk to your child's doctor about the risks of giving tezacaftor and ivacaftor to your child.

Tezacaftor and ivacaftor may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order a lab test before you begin your treatment to see whether your condition can be treated with tezacaftor and ivacaftor. Your doctor will also order certain lab tests before and during your treatment to check your body's response to tezacaftor and ivacaftor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand names

  • Symdeko®
Last Revised - 06/15/2026