Why get tested?
To detect elevated levels of ammonia in the blood, to help evaluate changes in consciousness, severe liver disease, and certain genetic urea cycle disorders; to support the diagnosis of hepatic encephalopathy and Reye’s syndrome

When to get tested?
When a patient experiences mental changes or lapses into a coma of unknown origin; when an infant or child experiences frequent vomiting and increased lethargy as a newborn or about a week after a viral illness

Sample required?
A blood sample drawn from a vein in your arm