Skip to Content

Drugs and the Liver


Danielle Tholey

, MD, Thomas Jefferson University Hospital

Last full review/revision Apr 2021| Content last modified Apr 2021

The body must process (chemically alter, or metabolize) drugs to be able to use and eliminate them. Most of this processing occurs in the liver, done by liver enzymes. Thus, drugs and the liver can affect each other in several ways:

  • Liver disorders can change the way a drug is metabolized.
  • Some drugs can damage the liver.
  • Many factors (such as foods eaten, a person's genetic makeup, and use of other drugs) can affect the way the liver metabolizes drugs (see Factors Affecting Response to Drugs).

Drugs can affect how quickly certain other drugs are metabolized in the liver. If a drug is metabolized more quickly, it may be broken down and eliminated before it can do what it is supposed to do. In slower drug metabolism, side effects are more likely.

More Information about Drugs and the Liver

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • U.S. Food and Drug Administration: Sometimes Drugs and the Liver Don't Mix: Consumer-friendly information on how to prevent the potentially toxic effects of drug use on the liver.

Copyright © 2021 Merck & Co., Inc., known as MSD outside of the US, Kenilworth, New Jersey, USA. All rights reserved. Merck Manual Disclaimer