Lactic Acidosis: Why Too Much Lactic Acid in Your Blood Is Dangerous

Do you remember chemistry class? Maybe something about acids and bases rings a bell. The balance between acids and bases is called the pH level. The normal pH of human blood sits between 7.35 and 7.45. Too much acid decreases the pH, and too much base increases it. If blood pH is abnormal, the body can’t function properly.

Lactic acidosis affects the blood’s pH, and it’s a serious health problem. Learn more about what it is, as well as its causes, diagnosis, and treatment.

What is lactic acidosis?

Lactic acidosis occurs when too much lactic acid (also known as “lactate”) builds up in the bloodstream and changes the pH.

Lactic acid is produced by many parts of the body on a daily basis. Lactic acid itself isn’t dangerous. In fact, your muscles can produce lactic acid during intense workouts. But your kidneys and liver can break it down.

Lactic acidosis happens when there’s too much lactic acid, because your body has produced too much or it’s unable to get rid of it.

There are many different causes of lactic acidosis, and treatment depends on the cause. Left untreated, lactic acidosis can be life-threatening.

What causes lactic acidosis?

Normally, the liver and kidneys get rid of lactic acid after it’s produced, keeping blood pH within the normal range.

Lactic acidosis occurs when the amount of lactic acid overwhelms the ability of the liver and kidneys to get rid of it. Blood pH drops, and organs struggle to work properly.

People with liver or kidney problems may develop lactic acidosis more easily than others. This is because they have a reduced ability to get rid of lactic acid.

What are the symptoms of lactic acidosis?

Symptoms of lactic acidosis aren’t due to lactic acid itself. Rather, they’re due to the fact that there’s too much acid in the blood. Sometimes, people with lactic acidosis will have no symptoms at all. But when symptoms occur, they might include:

• Confusion

• Feelings of tiredness and weakness

• Fast heartbeat

• Rapid breathing

• Lack of appetite, nausea, or vomiting

In Type A lactic acidosis, people also have signs and symptoms of hypoperfusion, such as:

• Low blood pressure

• Cool or clammy extremities

• Decreased urination

• Fast heartbeat

How do you diagnose lactic acidosis?

Lactic acidosis is always caused by some other problem, and those problems make people quite sick. So, lactic acidosis is typically diagnosed in a hospital, not a doctor’s office.

Lactic acidosis is easy to diagnose. Simple blood tests can measure the levels of lactic acid in the blood and the blood pH. The tricky part is knowing when to order these tests. In type A lactic acidosis, symptoms of hypoperfusion (like low blood pressure) provide clues. But Type B lactic acidosis requires a little more detective work.

How do you treat lactic acidosis?

To treat lactic acidosis, healthcare professionals treat the underlying cause. By treating the underlying cause, the production of lactic acid slows down, and the body has time to get rid of it. Here are examples of treatments:

• If a poison causes lactic acidosis, they’ll reverse the poisoning.

• If severe infection with septic shock is the problem, they’ll treat the infection.

• If heart failure is the problem, they’ll treat the heart failure.

In addition to addressing the underlying cause, treatment also involves IV fluids and supplemental oxygen. Lactic acidosis is typically treated in a hospital because people with lactic acidosis are quite ill.

How do you prevent lactic acidosis?

Taking certain steps can help you prevent lactic acidosis, especially if you’re at greater risk. Here are some prevention tips:

• Drink enough water to stay hydrated.

• Take your medications exactly as prescribed.

• Make sure all prescribers and pharmacists have your current medication list.

People who are at greater risk for lactic acidosis should be aware of signs and symptoms. This will allow them to seek treatment early. This includes people who:

• Have kidney and/or liver disease

• Have a history of lactic acidosis

• Are susceptible to dehydration or infection

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Written by:

Samantha C. Shapiro, MD

Samantha Shapiro, MD, is a board-certified rheumatologist and internist with expertise in autoimmune and inflammatory conditions. She founded the division of rheumatology at Dell Medical School at The University of Texas at Austin.

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

Reviewed by:

Mandy Armitage, MD

Mandy Armitage, MD, has combined clinical medicine with her passion for education and content development for many years. She is co-executive director at Nonclinical Physicians Network and has served as medical director for the health technology companies HealthLoop (now Get Well) and Doximity.

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