Ivacaftor/Strong and Moderate CYP3A4 Inhibitors Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Some medicines may slow down how quickly your liver processes ivacaftor.

What might happen:

The amount of ivacaftor in your blood may increase and cause more side effects than normally expected.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Your doctor may want to adjust the dose of your ivacaftor while you are taking your other medicine. Let your doctor know right away if you have any pain or discomfort in the upper right stomach (abdominal) area, yellowing of the skin or eyes, loss of appetite, nausea or vomiting, or dark/amber-colored urine.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

  • 1.Kalydeco (ivacaftor) US prescribing information. Vertex Pharmaceuticals Incorporated March, 2015.
  • 2.Liddy AM, McLaughlin G, Schmitz S, D'Arcy DM, Barry MG. The Pharmacokinetic Interaction between Ivacaftor and Ritonavir in Healthy Volunteers. Br J Clin Pharmacol 2017 May 06.
  • 3.US Food and Drug Administration (FDA). Drug Development and Drug Interactions: Table of Substrates, Inhibitors and Inducers. Available at: http://www.fda.gov/Drugs/DevelopmentApprovalProcess/DevelopmentResources/D rugInteractionsLabeling/ucm093664.htm. Updated 08/05/2011.
  • 4.Flockhart DA. Drug Interactions: Cytochrome P450 Drug Interaction Table. Indiana University School of Medicine. Available at: http://medicine.iupui.edu/clinpharm/ddis/table.aspx August 18, 2011.
  • 5.This information is based on or an extract from the UW Metabolism and Transport Drug Interaction Database (DIDB) Platform, Copyright University of Washington 1999-2014..