Lactic acidosis occurs when the body produces too much lactic acid and cannot metabolize it quickly enough. The condition can be a medical emergency.

The onset of lactic acidosis might be rapid and occur within minutes or hours, or gradual, happening over a period of days. The best way to treat lactic acidosis is to determine the cause.

Untreated lactic acidosis can result in severe and life threatening complications. In some instances, these can escalate rapidly.

Typically, symptoms of lactic acidosis do not stand out as distinct on their own but can be indicative of a variety of health issues.

However, some symptoms known to occur in lactic acidosis indicate a medical emergency.

These include:

  • disorientation
  • yellow skin or eyes, known as jaundice
  • shallow, rapid, or other breathing issues
  • rapid heart rate

Other symptoms include:

  • muscle pains or cramping
  • overall body discomfort
  • abdominal pain and discomfort
  • body weakness
  • fatigue, lethargy, and unusual sleepiness
  • reduced appetite
  • diarrhea
  • nausea and vomiting
  • headaches

Anyone who experiences one or more of these symptoms should call 911 or go to an emergency room immediately.

The most common causes of lactic acidosis are:

Other causes of lactic acidosis include:

Kidney conditions

Lactic acidosis can occur in people whose kidneys are unable to get rid of excess acid.

Even when not related to just a kidney condition, some people’s bodies make excess lactic acid and are unable to balance it out.


Lactic acidosis may develop in people with type 1 and 2 diabetes, especially if their condition is not well-managed.

There have been reports of lactic acidosis in people who take metformin, which is a standard noninsulin medication for treating type 2 diabetes. However, the incidence is low, with equal to or less than 10 cases per 100,000 patient-years of using the drug, according to a 2014 report in the journal Metabolism.

The incidence of lactic acidosis is higher in people with diabetes who also have other conditions, such as congestive heart failure and kidney disease. For these people, lactic acidosis indicates a poor outlook.

One 2015 report highlighted the case of a 49-year-old man with type 2 diabetes and congestive heart failure who arrived at an emergency department with difficulty breathing.

Within a couple of hours, he developed severe metabolic acidosis with high lactate concentrations. The man probably had lactic acidosis upon arrival to the hospital, which then quickly escalated.

Doctors changed the man’s daily metformin prescription to the maximum allowed a few weeks before the hospital admission.

Metformin was determined to be the potential cause of his lactic acidosis, considering his comorbid diseases, his health when he arrived at the hospital, and previous prescribed medication.

HIV treatments

Lactic acidosis can be a serious complication of antiretroviral therapy that prevents the replication of HIV.

Antiretroviral treatments make it more difficult for the body to stay within a typical level of lactate acid, so those people taking some antiretroviral therapies for HIV are at a higher risk for lactic acidosis.


In cases of people who are healthy, lactic acidosis can occur after strenuous physical exercise.

In these cases, the condition is temporary and the result of the body needing more oxygen to keep up with the amount of lactate building up in the blood.

When this mismatch occurs during intense exercise, symptoms may include a burning feeling in the muscles, nausea, and weakness.


There has been evidence connecting excessive alcohol consumption to a subtype of lactic acidosis called alcohol associated lactic acidosis.

A higher incidence of this type of lactic acidosis is associated with people who are critically ill, including those with sepsis, which is often a life threatening complication of infection.

Doctors can halt lactic acidosis by treating the underlying cause, potentially allowing the metabolization of the excess lactic acid.

While a doctor is trying to find the underlying cause of lactic acidosis or cannot immediately find the exact cause, they will provide treatments to support oxygen delivery and circulation.

Treatments can include:

  • IV fluid to promote circulation
  • oxygen via a face mask or another way
  • positive pressure ventilation to deliver oxygen to the lungs
  • vitamin therapy
  • hemodialysis with bicarbonate

Individuals who experience lactic acidosis while exercising can stop what they are doing, rehydrate by drinking water, and rest.

For some people, lactic acidosis is a temporary condition that they can treat successfully. However, it may be more complicated if lactic acidosis is part of other health conditions. In this case, successful treatment will depend on the management of their other health complications.

Complications of untreated lactic acidosis include:

  • irregular heart rhythm
  • unconsciousness or coma
  • shock
  • major organ failure

An individual can minimize the risk of complications by keeping any underlying medical conditions stable with correct treatments.

There are two types of lactic acidosis:

Type A

Type A lactic acidosis is related to tissue hypoxia, where the body is deficient in oxygen. It is also a characteristic of critical illness, such as sepsis and septic shock, or acute medical disease states, including those involving the cardiovascular system and liver.

Type B

Type B lactic acidosis is not related to tissue hypoxia and can be due to health conditions such as renal disease and certain cancers.

Type B also includes exercise-induced lactic acidosis due to an increased oxygen requirement.

Type B has a link to the use of some medications, including those for treating type 2 diabetes and HIV.

Chronic alcoholism and chronic liver disease can also be causes of type B lactic acidosis.

A doctor can confirm lactic acidosis by checking the lactate level in the blood, which will be higher than usual.

Other laboratory tests can also determine the cause or causes of lactic acidosis and identify other potential dysfunction within the body.

Blood samples are usually from a vein but may sometimes be from an artery.

Prevention of lactic acidosis is possible by managing its potential causes.

Anyone with diabetes, HIV, heart failure, liver disease, or kidney issues should work with their doctor to manage their conditions and take all medications as prescribed.

A person who experiences adverse reactions to diabetes or HIV medications should inform their doctor immediately.

Keeping hydrated, balancing resting and working out, and avoiding strenuous activity when not feeling well, can help avoid exercise-induced lactic acidosis.

Lastly, it is important not to misuse alcohol. Anyone with alcohol concerns can seek help from family, friends, their doctor, a therapist, or through a rehabilitation 12-step program.

Lactic acidosis is not necessarily a medical emergency when caused by overexercising. If left untreated, lactic acidosis is a medical emergency and may even be life-threatening.

The outlook for lactic acidosis will depend on its underlying cause. A timely diagnosis and treatment of the underlying cause potentially will lead to a full recovery.