Loss of liver or kidney function impairs your body's ability to rid itself of toxins, or foreign substances, so medications can build up in the body at higher dosages than intended. According to Bona Benjamin of the American Society of Health-System Pharmacists, a common -- and often serious or fatal -- mistake that doctors make is not decreasing medication dosages when patients begin to suffer impaired kidney or liver function. There are many medications that doctors shouldn't prescribe without first ordering liver and kidney function tests, but safety studies show that's often not happening.
How to avoid it: When you bring home a new prescription, read the fine print to see if liver or kidney function is mentioned. If so, ask your doctor if you've had recent liver and kidney function screenings.
