Am J Emerg Med. 2018 Sep;36(9):1570-1576. doi: 10.1016/j.ajem.2018.01.032. Epub 2018 Jan 10. Impact of intestinal mannitol on hyperammonemia, oxidative stress and severity of hepatic encephalopathy in the ED. Montes-Cortés DH1, Novelo-Del Valle JL2, Olivares-Corichi IM3, Rosas-Barrientos JV4, Jara LJ5, Cruz-Domínguez MP6. Author information Abstract Hyperammonemia results from hepatic inability to remove nitrogenous products generated by protein metabolism of intestinal microbiota, which leads to hepatic encephalopathy (HE) in chronic liver disease (CLD). In ammonium neurotoxicity, oxidative stress (OxS) plays a pathogenic role. Our objective was to evaluate if intestinal mannitol is as effective and safe as conventional treatment for diminishing hyperammonemia, OxS, and HE in patients with CLD. MATERIAL AND METHODS: We included 30 patients with HE classified by "Haven Criteria for Hepatic Encephalopathy". They were randomized into two groups: 1) Mannitol Group (MG) with mannitol 20% administered into the intestine by an enema, 2) conventional group (CG) with lactulose 40 g enema both substances were diluted in 800 mL of double distilled solution every 6 h; all patients received neomycin. We evaluated ammonia concentration, plasma oxidative stress, HE severity, intestinal discomfort and adverse effects. RESULTS: Hyperammonemia (171 ± 104 vs 79 ± 49 μmol ammonia/L, p