This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Page, R. L. Articles by Lindenfeld, J. Search for Related Content PubMed PubMed Citation Articles by Page, R. L., II Articles by Lindenfeld, J. Pubmed/NCBI databases Substance via MeSH Medline Plus Health Information Heart Transplantation Related Collections Transplantation CV surgery: transplantation, ventricular assistance, cardiomyopathy

(Circulation. 2005;111:230-239.)
© 2005 American Heart Association, Inc.

New Drugs and Technologies

Drug Therapy in the Heart Transplant Recipient

Part IV: Drug–Drug Interactions

Robert L. Page, II, PharmD; Geraldine G. Miller, MD; JoAnn Lindenfeld, MD

From the Department of Clinical Pharmacy (R.L.P.) and Division of Cardiology and Center for Women’s Health Research (J.L.), University of Colorado Health Sciences Center, Denver, Colo, and Division of Infectious Diseases (G.G.M.), Vanderbilt University, Nashville, Tenn.

Correspondence to JoAnn Lindenfeld, MD, Division of Cardiology, University of Colorado Health Sciences Center, 4200 E Ninth Ave, B-130, Denver, CO 80262. E-mail joann.lindenfeld@UCHSC.edu

Received March 16, 2004; revision received July 23, 2004; accepted September 30, 2004.

Key Words: transplantation • drugs • immunology • rejection

An extract of the first 250 words of the full text is provided, because this article has no abstract.

	Introduction

 
With improving survival, the heart transplant recipient faces an increasing number of medical problems caused by both aging and the cumulative complications of immunosuppressive drugs.¹ The availability of new drugs to treat infection, obesity, hypertension, hyperlipidemia, renal insufficiency, diabetes, osteoporosis, gout, and malignancies has resulted in the heart transplant recipient and their physicians facing an almost overwhelming number of important drug–drug interactions. In parts 1 through 3 of this series, we reviewed commonly used immunosuppressive drugs and their pharmacology, as well as the common medical problems faced by the heart transplant recipient. In this article, we provide an overview of the mechanisms of common and important potential drug–drug interactions and guidelines for avoiding these interactions.

	Principles of Drug–Drug Interactions

 
The risk for drug–drug interactions is increased by advanced age, polypharmacy, medications with a narrow therapeutic index, or medications requiring intensive monitoring. All of these factors except advanced age are present in the heart transplant recipient. A 10-fold interpatient variability may exist in the magnitude of a drug interaction resulting from patient-related and drug-related factors.²

Patient-related factors predisposing to drug interactions include concomitant diseases, genetics, diet, and environmental exposures. For example, commonly used immunosuppressants, antifungal agents, and lipid-lowering medications are metabolized through the cytochrome P450 (CYP450) enzyme system and effluxed from cells by the multiple drug resistance transporter protein p-glycoprotein (P-gp). Both systems are found in the liver and gastrointestinal tract and exhibit genetic polymorphism.² The CYP450 enzymes belong to a superfamily of oxygenases; the primary purpose of these oxygenases is to add a functional . . . [Full Text of this Article]

This article has been cited by other articles:

				N. Z. Sulemanjee, R. Merla, S. D. Lick, S. M. Aunon, M. Taylor, M. Manson, L. S.C. Czer, and E. R. Schwarz The First Year Post-Heart Transplantation: Use of Immunosuppressive Drugs and Early Complications Journal of Cardiovascular Pharmacology and Therapeutics, March 1, 2008; 13(1): 13 - 31. [Abstract] [PDF]

				J. R Burton, I. Burton, and G. J Pearson Clopidogrel-Precipitated Rhabdomyolysis in a Stable Heart Transplant Patient Ann. Pharmacother., January 1, 2007; 41(1): 133 - 137. [Abstract] [Full Text] [PDF]