Drugs and the ageing liver

A recent WHO estimate suggests that ca. 20% of the population in developed countries are 'elderly' and that 50% of all drugs are prescribed to individuals over age 65 years. It is now well recognised that the elderly are particularly susceptible to drug adverse reactions in general [1-3], and there are increasing suggestions that 'a number of hepatic adverse reactions to drugs may be age-related [4,5]. It is therefore appropriate to examine the changes which occur in human hepatic drug metabolism in advanced age and to assess the evidence for increased sensitivity to hepatic .adverse drug reactions in the elderly. The important liver-related physiological changes which may affect hepatic disposition of drugs which advanced age include reduced liver blood flow, and progressive decrease in liver size and weight both absolutely and relative to total body weight [6]. Other age-related changes which may affect drug pharmacokinetics include decrease in lean body mass with a proportionate increase in fat; glomerular filtration rate declines by 1-2% per year over age 65.