Key Pharmacologic Principles and Drug-Drug Interactions in HIV Patient Care

  • Authors: Amanda H. Corbett, PharmD, BCPS, FCCP; Colin I. Sheffield, PharmD (More Info)
  • Section Editor: Eric S. Daar, MD
  • Editors in Chief: Daniel R. Kuritzkes, MD; Joseph J. Eron, Jr., MD
  • Last Reviewed: 6/3/19 (What's New)


  • Interactions between antiretrovirals and herbal and dietary supplements are often difficult to predict
  • Potential for decreased activity of antiretrovirals with garlic supplements, St. John’s wort, and ascorbic acid (vitamin C)[Piscitelli 2000; Piscitelli 2002; Slain 2005]
  • Coadministration of St. John’s wort and garlic supplements with any antiretroviral that is metabolized by CYP 450 enzymes or a substrate of P-gp is contraindicated[DHHS ART; Fasinu 2015; Stolbach 2015]
  • Polyvalent Cations

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