Why is Ammonia High? Causes, Symptoms, and What to Do

Discover why ammonia levels may be high, the symptoms involved, and what steps to take next. Understand when to consult a healthcare professional.

Aug 12, 2026 3 min read

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Ammonia is a waste product that the liver typically clears from the body. When ammonia levels are high in the blood, it can indicate an underlying health issue. Understanding the causes and symptoms of high ammonia levels can help you take appropriate actions and decide when to consult a healthcare provider.

What is Ammonia?

Ammonia is a compound made up of nitrogen and hydrogen. It is produced naturally in the body as a byproduct of protein metabolism. Normally, the liver converts ammonia into urea, which is then excreted by the kidneys. In adults, the typical range for ammonia levels in the blood is approximately 10 to 45 micromoles per liter (~10–45 umol/L).

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Causes of High Ammonia Levels

High ammonia levels can occur due to various reasons, including:

  • Liver disease: Conditions like cirrhosis or hepatitis can impair the liver's ability to convert ammonia into urea, leading to elevated levels.
  • Kidney dysfunction: When the kidneys are not working well, they may not effectively remove urea, indirectly causing ammonia to build up.
  • Genetic disorders: Some inherited conditions, such as urea cycle disorders, affect how the body processes ammonia.
  • Infections: Severe infections can sometimes lead to liver dysfunction and high ammonia levels.
  • Medications and toxins: Certain drugs and toxins can impair liver function, leading to increased ammonia levels.

Symptoms of High Ammonia Levels

Symptoms of high ammonia levels can vary depending on the underlying cause and severity. Common symptoms include:

  • Confusion or disorientation
  • Fatigue
  • Difficulty thinking clearly
  • Tremors or shaking
  • Behavioral changes

In severe cases, high ammonia levels can lead to a condition known as hepatic encephalopathy, where the brain is affected due to liver failure in removing ammonia.

What To Do If Your Ammonia Levels Are High

If your ammonia levels are high, your healthcare provider will likely investigate the underlying cause. They may recommend lifestyle changes, medication, or further testing to monitor your liver and kidney function. Treatment will depend on the specific cause of the elevated ammonia levels.

Frequently asked questions

What are normal ammonia levels?

Normal ammonia levels in adults range from about 10 to 45 micromoles per liter (~10–45 umol/L).

Can high ammonia levels be dangerous?

Yes, high ammonia levels can be dangerous, particularly if they lead to hepatic encephalopathy, a condition where the brain is affected due to liver failure.

How are high ammonia levels diagnosed?

High ammonia levels are diagnosed through a blood test that measures the concentration of ammonia in the blood.

Can diet affect ammonia levels?

Yes, a high-protein diet can increase ammonia production since ammonia is a byproduct of protein metabolism.

Are there treatments for high ammonia levels?

Treatment depends on the underlying cause but may include medications to reduce ammonia production or dietary changes to limit protein intake.

When to see a doctor

If you experience symptoms such as confusion, fatigue, or behavioral changes, it is important to consult a healthcare provider. These symptoms could indicate high ammonia levels and may require medical evaluation to determine the underlying cause.

High ammonia levels can be a sign of a serious underlying condition. Always consult with your healthcare provider to determine the best course of action for your specific situation.

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