The Ammonia test measures the level of ammonia in the blood, a waste product that is normally removed by the liver. Elevated ammonia levels can indicate liver dysfunction, especially in cases of cirrhosis, hepatitis, or liver failure. High levels may also be associated with kidney problems, urea cycle disorders, or severe infections. This test helps assess the function of the liver and kidneys and can guide treatment for conditions like hepatic encephalopathy. A blood sample is required for this test.