What Is a Lactic Acid Blood Test?

Medically Reviewed by Melinda Ratini, MS, DO on August 20, 2021
2 min read

It’s a test that measures the amount of lactic acid (also called “lactate”) in your blood.

This acid is made in muscle cells and red blood cells. It forms when your body turns food into energy. Your body relies on this energy when its oxygen levels are low. Oxygen levels might drop during an intense workout or when you have an infection or disease. Once you finish your workout or recover from the illness, your lactic acid level tends to go back to normal.

But sometimes, it doesn't.

Higher-than-normal lactic acid levels can lead to a condition called lactic acidosis. If it’s severe enough, it can upset your body’s pH balance, which indicates the level of acid in your blood. Lactic acidosis can lead to these symptoms:

It’s a simple blood test. Your doctor will draw blood from a vein or artery using a needle. In rare cases, they may take a sample of cerebrospinal fluid from your spinal column during a procedure called a spinal tap.

Normally, you don’t have to adjust your routine to prepare for the test.

If your lactic acid level is normal, you don’t have lactic acidosis. Your cells are making enough oxygen. It also tells your doctor that something other than lactic acidosis is causing your symptoms. They’ll likely order other tests to find out what it is.

If your lactic acid level is high, it could be caused by a number of things. Most often, it’s because you have a condition that makes it hard for you to breathe in enough oxygen. Some of these conditions could include:

A higher-than-normal lactic acid level in your blood can also be a sign of problems with your metabolism. And, your body might need more oxygen than normal because you have one of the following conditions:

Elevated lactic acid levels can also mean you’re not getting enough vitamin B1.