Protease Inhibitors/Astemizole; Terfenadine
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:
Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, your body may not process your antihistamine properly.
What might happen:
The blood levels of your antihistamine may increase and cause an irregular heartbeat.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. It may be necessary to change you to a different antihistamine. Do not start, stop, or change the dosage of any medicine before checking with them first.
References:
1.Agenerase (amprenavir) US prescribing information. Glaxo Wellcome, Inc. April, 1999.
2.Prezista (darunavir) US prescribing information. Tibotec Inc. June, 2006.
3.Kaletra (lopinavir/ritonavir tablets) US prescribing information. Abbott Laboratories September, 2007.
4.Norvir (ritonavir) US prescribing information. Abbott Laboratories March, 1997.
5.Aptivus (tipranavir) US prescribing information. Boehringer Ingelheim Pharmaceuticals, Inc. June, 2007.
6.Crixivan (indinavir sulfate) US prescribing information. Merck & Co., Inc. January, 2004.
7.Viracept (nelfinavir mesylate) US prescribing information. Agouron Pharmaceuticals, Inc. March, 1997.
8.Fortovase (saquinavir) US prescribing information. Roche Laboratories, Inc. December, 2004.
9.Invirase (saquinavir mesylate) US prescribing information. Roche Laboratories, Inc. July, 2007.
10.Seldane (terfenadine) US prescribing information. Hoechst-Marion Roussel September, 1997.
11.Allegra (fexofenadine hydrochloride) US prescribing information. Sanofi-Aventis U.S. LLC October, 2006.
12.Claritin (loratadine) US prescribing information. Schering-Plough Corporation January, 1997.
13.Lexiva (fosamprenavir calcium) US prescribing information. GlaxoSmithKline October, 2003.
