Adjusting Medications with Kidney Failure

How Kidney Failure Affects My Medications?

Introduction

The kidneys (along with the liver) play a major role in breaking down and removing drug from the body. Kidney disease often requires stopping or adjusting the dosages of many medications.

Reasons for Adjustments

There are a number of reasons why kidney disease can result in a need to change your medications. They usually result from changes in:

• Absorption: Absorption of drugs by the gastrointestinal (GI) system can be decreased in kidney failure. This can be particularly problematic for people with diabetes or already taking a large number of medicines.
• Distribution: After a drug is ingested, it is dispersed throughout the body. Some drugs bind to protein in blood which can be decreased with protein losing kidney diseases. Other drugs stay primarily in body water, which can be affected by dehydration or edema, which are more common with kidney disease.
• Break Down: The chemical reactions that break down drugs and their toxic byproducts often slow down with kidney failure. As a result, the active or toxic parts accumulate. This probably explains that high rate of drug reactions in kidney failure.
• Elimination: The removal of many drugs and their breakdown products are dependent on the filtering ability (GFR) of the kidneys. When the GFR decreases, less is removed from the body. The kidneys ability to secrete drugs that aren’t easily filtered is often diminished as the GFR falls as well.