Glomerular Filtration Rate (GFR)

What is Glomerular Filtration Rate (GFR)?

Glomerular filtration refers how much blood passes through the “glomeruli”—tiny filters that filter waste from our blood—per minute. The result is called the glomerular filtration rate or GFR, which is a measure of kidney function and determines what stage of kidney disease you might be in. A normal rate is 90 to 120 milliliters or above per minute while a rate of 30 or below indicates kidney failure. As we age, our GFR goes down naturally whether or not we have kidney disease.

How GFR test is done and who should get it

GFR testing requires a blood sample, usually drawn from a vein in your arm. Your doctor will provide guidance on how to prepare for your test and you may be asked not to take certain medications beforehand. Once the test results come in, your doctor will review your lab results for creatine levels (creatine is a waste product in the blood) and will also take into consideration other factors such as your age, height, weight, ethnicity and gender, to determine your GFR.

Once your doctor knows your GFR, he or she can make diet, lifestyle and medication recommendations, and can suggest treatment options. If you have kidney disease or are at risk, you will need to get your GFR checked regularly to assess whether the disease has progressed.

The GFR test is usually recommended for people with chronic kidney disease or who are more at risk due to diabetes, family history, heart disease, high blood pressure, or frequent urinary infections.


Kidney Care (Nephrology)

Our nephrologists, located throughout the Philadelphia suburbs, will medically manage your kidney conditions and develop a treatment plan based on your specific needs.