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:
Bosentan may speed up how quickly your liver processes hormonal contraceptive agents.
What might happen:
Hormonal contraceptive products (such as "the pill", the "mini-pill", Norplant, birth control injections, and the patch) may not prevent you from becoming pregnant while you are taking bosentan. If you take bosentan while pregnant, it may cause birth defects.
What you should do about this interaction:
You should not rely on a hormonal contraceptive agent as your only method of birth control while taking bosentan. Discuss birth control options with the doctor that prescribed bosentan for you and with your gynecologist (OB/GYN). Be sure to undergo a pregnancy test every month. If you think that you may be pregnant, concact your doctor right away.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.Tracleer (bosentan) US prescribing information. Actelion Pharmaceuticals US, Inc. October, 2012.
2.van Giersbergen PL, Halabi A, Dingemanse J. Pharmacokinetic interaction between bosentan and the oral contraceptives norethisterone and ethinyl estradiol. Int J Clin Pharmacol Ther 2006 Mar;44(3):113-8.