Drug metabolism and drug interactions in the elderly

Best Pract Res Clin Gastroenterol. 2001 Dec;15(6):897-918. doi: 10.1053/bega.2001.0249.


In the elderly concomitant use of several drugs (polypharmacy) is very common. Thus, the risk for drug interactions might be increased in this population. Since most drugs are hepatically eliminated by various metabolic pathways, liver function has to be considered as an additional factor modifying drug response. This chapter focuses on the hepatic mechanisms of interactions, especially on various inhibitors and inducers of the most important cytochrome P450 isoenzymes involved in drug metabolism. In addition, age-dependent changes in liver function are addressed. Based on pharmacokinetic results with different probe drugs, some inconsistencies in this area are discussed. The most important metabolic drug-drug interactions are independent of the age of the patients. However, since elderly patients consume a greater proportional share of drugs, they represent a population at risk for interactions. Awareness of this clinical problem may help to diminish those risks.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Aged / physiology*
  • Cytochrome P-450 Enzyme System / metabolism*
  • Drug Interactions / physiology*
  • Humans
  • Liver / metabolism
  • Pharmaceutical Preparations / metabolism*
  • Pharmacokinetics
  • Risk Factors


  • Pharmaceutical Preparations
  • Cytochrome P-450 Enzyme System