Some painkillers may harm kidneys
If you regularly take over-the-counter painkillers, especially for a long period of time, consider checking with your doctor about a kidney function test.
OTC pain and fever reducers are not dangerous. But, over time, some painkillers can have negative effects.
Some examples of painkillers that are metabolized by the kidneys are ibuprofen and naproxen sodium. But others can have an impact on kidneys too.
If you already have impaired kidney function, be absolutely sure you are following the doctor’s orders on painkillers.
If you have taken painkillers over time, you might want to ask a doctor about it.
Your doctor can order a simple blood test called a serum creatinine level. This test measures the amount of a waste product in your blood that is normally removed by your kidneys. If your kidneys are not working as well as they should, the creatinine level will be increased in your blood. The results of the serum creatinine test can be used to estimate your glomerular filtration rate (GFR). Your GFR number tells your doctor how much kidney function you have.
Your doctor can also order a urine test for the presence of protein. Persistent protein in the urine may be an early indication of kidney damage.

Here’s how kidneys work
Every day your kidneys go about their work of removing excess fluid and waste from your blood. You probably never think about them. But you should.
In addition to filtering waste, the kidneys have several important jobs to do. Consider this: They produce the two hormones needed to make red blood cells and regulate blood pressure, and they produce the active form of vitamin D, which helps maintain calcium for bones and other body functions.
Each kidney has millions of tiny nephrons that act as filters. Beginning about age 40, a natural loss of nephrons occurs, but because there are so many, that doesn’t cause problems unless other factors are present. If you have high blood pressure, diabetes, or both, some nephrons will lose their ability to filter blood.
In addition to controlling diabetes and blood pressure, you can protect your kidneys with these steps.
*Get treatment for strep throat. When streptococcus invades the kidneys of adults, it can lead to kidney problems and kidney failure in some cases.
* Know what’s in “natural herb supplements.” Some substances can work like prescription drugs. Patients taking blood thinners should know that garlic, ginger, Ginkgo biloba, and ginseng all contain natural anticoagulants. They could cause internal bleeding in people taking blood thinners.