Effect of L-Carnitine Upon Ammonia Tolerance Test in Cirrhotic Patients

Review article: the current pharmacological therapies for hepatic encephalopathy

“…In 150 patients with mild or moderate HE, levocarnitine significantly reduced serum ammonia levels and improved mental status compared with placebo ( P < 0.05) 54 . However, in an earlier clinical study, following rectal ammonium administration in patients with cirrhosis, levocarnitine provided no significant protection against increases in ammonia levels compared with placebo 55 …”

L-carnitine in Hyperammonemia and Hepatic Encephalopathy

“…Clinical studies in humans with HE have only been performed by a few groups to date. Nevertheless, in initial clinical studies (del Olmo et al, 1990), the effect of L-carnitine on HA in patients with cirrhosis, subjected to a rectal ammonium overload test, was investigated. On comparing 40 cirrhotic patients given L-carnitine with 40 control cirrhotics given a placebo, no significant differences were observed in ammonium levels.…”

Non-absorbable disaccharides and antibacterials are the treatment of choice for hepatic encephalopathy

“…As the ratio of aromatic amino acids to BCCAs is increased in pts with liver disease, restoring the appropriate balance has theoretical benefits A meta-analysis of 5 trials suggested that parenteral BCAA therapy improves mental recovery in pts with cirrhosis and acute HE [32] A recent systematic review of 11 RCTs concluded that there was no convincing evidence for the use of oral BCAAs in pts with HE [33] Dopamine receptor agonists Dopamine transmission may be affected by manganese accumulation in the basal ganglia of pts with cirrhosis Little clinical data are currently available Elevated prolactin levels in pts receiving bromocriptine is a concern Levocarnitine May be protective against ammonia neurotoxicity according to animal data Reduced serum ammonia levels and improved mental status compared with placebo in pts with mild to moderate HE, [34] but did not reduce ammonia levels in a second study [35] Memantine NMDA receptor antagonist approved for the treatment of Alzheimer's disease dementia Overactivity of the NMDA receptor has been demonstrated in a rat model of encephalopathy Shown to improve clinical grading and other markers of encephalopathy in rats…”