Don’t request blood ammonium measurement for diagnosis or management of hepatic encephalopathy (HE) in patients with chronic hepatopathy.

Type of practice

Laboratory tests

High blood ammonium alone adds no information in the diagnosis, staging, and prognosis of hepatic encephalopathy (HE) in patients with chronic hepatopathy, and ammonium concentration rarely correlates with symptoms severity and outcomes.


1. Arora S, Martin CL, Herbert M. Myth: interpretation of a single ammonia level in patients with chronic liver disease can confirm or rule out hepatic encephalopathy. CJEM 2006;8:433-5. doi: 10.1017/s148180350001424x. PMID: 17209493.
2. Gundling F, Seidl H, Schmidt T,et al. Blood ammonia level in liver cirrhosis: a conditio sine qua non to confirm hepatic encephalopathy? Eur J Gastroenterol Hepatol. 2008;20:246-247
3. Vilstrup H, Amodio P, Bajaj J, et al. Hepatic encephalopathy in chronic liver disease: 2014 Practice Guideline by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver. Hepatology 2014; 60: 715-35.
4. Ninan J, Feldman L. Ammonia levels and hepatic encephalopathy in patients with known chronic liver disease. J Hosp Med 2017; 12: 659-61.



Attention. Please note that these items are provided only for information and are not intended as a substitute for consultation with a clinician. Patients with any specific questions about the items on this list or their individual situation should consult their clinician.