Ammonia in blood plasma

In cases of impaired consciousness of unclear origin: drowsiness, confusion, coma, seizures - especially in patients with liver diseases.
In suspected hepatic encephalopathy: cirrhosis, fulminant hepatitis, hepatorenal syndrome, portosystemic shunts.
In newborns and children: suspected congenital metabolic disorders, especially ornithine cycle defects; hypoglycemia, vomiting, lethargy in the first days of life.
After taking potentially hepatotoxic drugs: valproic acid, anticonvulsants, chemotherapy.
For differential diagnosis: metabolic encephalopathy, poisoning, infections causing hyperammonemia (e.g., urease-positive urinary tract infections).