Effects of Liver Disorders on Drugs

ByDanielle Tholey, MD, Sidney Kimmel Medical College at Thomas Jefferson University
Reviewed/Revised Mar 2023
VIEW PROFESSIONAL VERSION

Liver disorders often change the effect of drugs on the body—for example, by changing

  • How much of the drug is absorbed from the intestine

  • How quickly and completely the liver metabolizes a drug—for example, changing the drug into an active form or into an inactive form (a form that has no effect on the body)

  • How much of the drug is transported throughout the body

  • How quickly the drug is eliminated from the body

  • How sensitive the body is to a drug's effects

(See also Drugs and the Liver.)

How liver disorders affect a drug depends on the particular drug. Liver disorders can increase the effects of some drugs and decrease the effects of others. The drug's effect is increased if the liver is less able to inactivate a drug. The drug's effect is decreased if the liver is less able to change the drug to an active form or if the liver makes the body less able to absorb a drug or to transport it throughout the body.

Did You Know...

  • Liver disorders can increase the effects of some drugs and decrease the effects of others.

A chronic liver disorder can make people more sensitive to the effects of certain drugs, even when the disorder does not increase the amount of drug in the body. For example, if people with certain liver disorders take even small doses of opioid pain relieverssedatives

Because liver disorders are complicated, doctors often cannot predict how they will affect a particular drug. Thus, adjusting drug doses for people who have a liver disorder can be difficult.

More Information

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

  1. 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.

Drugs Mentioned In This Article
quizzes_lightbulb_red
Test your KnowledgeTake a Quiz!
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID