Ammonia and Its Role in the Pathogenesis of Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a commonly encountered sequela of chronic liver disease and cirrhosis with significant associated morbidity and mortality. Although ammonia is implicated in the pathogenesis of HE, the exact underlying mechanisms still remain poorly understood. Its role in the urea cycle, astrocyte swelling, and glutamine and gamma-amino-n-butyric acid systems suggests that the pathogenesis is multifaceted. Greater understanding in its underlying mechanism may offer more targeted therapeutic options in the future, and thus further research is necessary to fully understand the pathogenesis of HE.