Why is an ammonia test done?
An ammonia test is done to:
- Check how well the liver is working, especially when symptoms of confusion, excessive sleepiness, coma, or hand tremor are present.
- Check the success of treatment for severe liver disease, such as cirrhosis.
- Help identify a childhood disorder called Reye syndrome that can damage the liver and the brain. Ammonia testing can also help predict the outcome (prognosis) of a diagnosed case of Reye syndrome.
- Help predict the outcome (prognosis) of a diagnosed case of acute liver failure.
- Check the level of ammonia in a person receiving high-calorie intravenous (I.V.) nutrition (hyperalimentation).
How is an ammonia test done?
A health professional uses a needle to take a blood sample, usually from the arm.
How do you prepare for an ammonia test?
In general, there is nothing you have to do before this test, unless your doctor tells you to.
What do the results of an ammonia test mean?
Normal
Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.
High values
High levels of ammonia in the blood may be caused by:
- Liver disease, such as cirrhosis or hepatitis.
- Reye syndrome.
- Heart failure.
- Kidney failure.
- Severe bleeding from the stomach or intestines.
High ammonia values in a baby may be present when the blood types of the baby and the parent who gave birth do not match (hemolytic disease of the newborn).
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