Metabolic acidosis happens when your blood becomes too acidic. This can result from other health conditions, such as diabetes that isn’t effectively controlled and kidney disease, among others.

When your body fluids contain too much acid, it’s known as acidosis. Acidosis occurs when your kidneys and lungs can’t keep your body’s pH in balance.

Many of the body’s processes produce acid. Your lungs and kidneys can usually compensate for slight pH imbalances, but problems with these organs can lead to excess acid accumulating in your body and blood.

The acidity of your blood is measured by determining its pH. A lower pH means that your blood is more acidic, while a higher pH means that your blood is more basic.

The pH of your blood should be around 7.4. Acidosis is characterized by a pH of 7.35 or lower. Alkalosis is characterized by a pH level of 7.45 or higher.

While seemingly slight, these numerical differences can be serious. Metabolic acidosis can lead to numerous health issues, and it can even be life threatening.

There are a few causes of metabolic acidosis. Metabolic acidosis starts in the kidneys instead of the lungs. It occurs when they can’t eliminate enough acid or when they get rid of too much base. There are four major forms of metabolic acidosis:

  • Diabetic acidosis, which occurs in people with diabetes that’s poorly controlled. If your body lacks enough insulin, ketones build up in your body and acidify your blood.
  • Hyperchloremic acidosis, which results from a loss of sodium bicarbonate. This base helps to keep the blood neutral. Both diarrhea and vomiting can cause this type of acidosis.
  • Lactic acidosis, which occurs when there’s too much lactic acid in your body. Causes can include chronic alcohol use, heart failure, cancer, seizures, liver failure, prolonged lack of oxygen, and low blood sugar. Even prolonged exercise can lead to lactic acid buildup.
  • Renal tubular acidosis, which occurs when the kidneys are unable to excrete acids into the urine. This causes the blood to become acidic.

Learn more about acid-base balance.

Factors that can contribute to your risk of metabolic acidosis include:

Some of the common symptoms of metabolic acidosis include the following:

  • rapid and shallow breathing
  • confusion
  • fatigue
  • headache
  • sleepiness
  • lack of appetite
  • jaundice
  • increased heart rate
  • breath that smells fruity, which is a sign of diabetic acidosis (ketoacidosis)

People with metabolic acidosis are often very ill and frequently end up in the emergency room. Early diagnosis can make a big difference in your recovery. Depending on what your doctor thinks might be causing your metabolic acidosis will help determine which tests they administer.

Anion gap

Doctors diagnose acidosis with a series of blood tests. One of the most common is to measure your anion gap. The anion gap is the difference between the positively and negatively charged electrolytes in your blood.

Electrolytes are naturally occurring substances like magnesium, sodium and calcium. They help control the equilibrium between acids and bases in your body. Electrolytes also have electrical charges.

If the difference between the oppositely charged electrolytes is too high or too low, it could signal to your doctor that something’s wrong.

Arterial blood gases

An arterial blood gas looks at the levels of oxygen and carbon dioxide in your blood. It also reveals your blood pH. A basic metabolic panel checks your kidney functioning. It also measures your calcium, protein, blood sugar, and electrolyte levels. If these tests are taken together, they can identify different types of acidosis.

Urine tests

If metabolic acidosis is suspected, you’ll need to give a urine sample. Doctors will check the pH to see if you’re properly eliminating acids and bases. Additional tests may be needed to determine the cause of your acidosis.

If you’re diagnosed with respiratory acidosis, your doctor will want to check the health of your lungs. This may involve a chest X-ray or a pulmonary function test.

Doctors usually need to know what’s causing your metabolic acidosis to determine how to treat it. The treatment metabolic acidosis can involve treating the root cause of the acid-base imbalance. The specific types of metabolic acidosis each have their own treatments that include:

  • Acidosis from kidney failure may be treated with sodium citrate.
  • A person with diabetes with ketoacidosis receive intravenous drip (IV) fluids and insulin to balance out their pH.
  • Lactic acidosis treatment might include bicarbonate supplements, IV fluids, oxygen, or antibiotics, depending on the cause.
  • People with hyperchloremic acidosis may be given oral sodium bicarbonate.

Bicarbonate

Sodium bicarbonate, or baking soda, is often given to people with certain types of metabolic acidosis. The chemical compound that’s often used to treat heartburn by neutralizing stomach acid.

When used to treat metabolic acidosis, it can help make your body’s fluids more alkaline, or raise the pH of your blood. Your doctor may give you sodium bicarbonate either by mouth or by IV.

A 2014 study showed it’s useful when your acidosis is caused by the lose of sodium bicarbonate in you system. That’s often associated with diarrhea.

According to a controlled trial published in 2019, metabolic acidosis bicarbonate is not only safe for people with kidney disease, but can also improve kidney function and your lifespan.

Without prompt treatment, acidosis may lead to the following health complications:

  • kidney stones
  • chronic kidney problems
  • kidney failure
  • bone disease
  • delayed growth

You can’t completely prevent acidosis.

You can do the following to reduce your risk of metabolic acidosis:

  • Stay hydrated. Drink plenty of water and other fluids.
  • If you’re a person with diabetes, manage your blood sugar levels.
  • If you use alcohol, consider cutting back. Chronic alcohol use can increase the buildup of lactic acid.

Some people fully recover from metabolic acidosis. Other people have problems with organ function, respiratory failure, and kidney failure. Severe metabolic acidosis can cause shock or even death.

How well you recover from metabolic acidosis depends on its cause. Fast, proper treatment also strongly influences your recovery.