There is no effective treatment available for hepatic encephalopathy at the moment; therefore we aimed to check the efficacy and safety of L-ornithine L-aspartate(LOLA). It provides critical substrates for ureagenesis and glutamine synthesis, the two primary mechanisms by which the body rids itself of excess ammonia. Ornithine is a specific activator of ornithine carbamyl transferase and carbamylphosphate synthetase, and, in addition, is a substrate for ureagenesis. These reactions are carried out mainly in the periportal portion of the hepatic lobules. Aspartate and ornithine, after conversion to alfa-ketoglutarate, are substrates for glutamine synthesis, which is performed exclusively by a small population of perivenous hepatocytes, the so-called perivenous scavenger cells. The ammonia lowering effect resulting from the stimulation of these two basic mechanisms of ammonia detoxification has been studied in animals and was confirmed in humans in clinical trials.