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At a Glance
Why Get Tested?
To detect an elevated level of ammonia in the blood that may be caused by severe liver disease, kidney failure, or certain rare genetic urea cycle disorders; to help investigate the cause of changes in behavior and consciousness; to support the diagnosis of hepatic encephalopathy or Reye syndrome
When to Get Tested?
When someone with liver disease or kidney failure experiences mental changes or lapses into a coma; when a newborn experiences frequent vomiting and increased lethargy or when a child has continuous vomiting and unusual sleepiness about a week after a viral illness, such as the flu or chickenpox
A blood sample drawn from a vein in your arm
Test Preparation Needed?
You should not smoke cigarettes prior to collection of the specimen.