Metabolic Brain Disease

, Volume 28, Issue 2, pp 193–199 | Cite as

Acetyl-L-carnitine in hepatic encephalopathy

Original Paper


Hepatic encephalopathy is a common complication of hepatic cirrhosis. The clinical diagnosis is based on two concurrent types of symptoms: impaired mental status and impaired neuromotor function. Impaired mental status is characterized by deterioration in mental status with psychomotor dysfunction, impaired memory, and increased reaction time, sensory abnormalities, poor concentration, disorientation and coma. Impaired neuromotor function include hyperreflexia, rigidity, myoclonus and asterixis. The pathogenesis of hepatic encephalopathy has not been clearly defined. The general consensus is that elevated levels of ammonia and an inflammatory response work in synergy to cause astrocyte to swell and fluid to accumulate in the brain which is thought to explain the symptoms of hepatic encephalopathy. Acetyl-L-carnitine, the short-chain ester of carnitine is endogenously produced within mitochondria and peroxisomes and is involved in the transport of acetyl-moieties across the membranes of these organelles. Acetyl-L-carnitine administration has shown the recovery of neuropsychological activities related to attention/concentration, visual scanning and tracking, psychomotor speed and mental flexibility, language short-term memory, attention, and computing ability. In fact, Acetyl-L-carnitine induces ureagenesis leading to decreased blood and brain ammonia levels. Acetyl-L-carnitine treatment decreases the severity of mental and physical fatigue, depression cognitive impairment and improves health-related quality of life. The aim of this review was to provide an explanation on the possible toxic effects of ammonia in HE and evaluate the potential clinical benefits of ALC.


L-carnitine Acetyl-L-carnitine Ammonia Hepatic encephalopathy Cirrhosis 



Michele Malaguarnera was supported by the International PhD program in Neuropharmacology of the University of Catania.

Competing interests

The author declares that he has no competing interests


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.International Ph.D. Program in NeuropharmacologyUniversity of CataniaCataniaItaly
  2. 2.Research Center “The Great Senescence”University of CataniaCataniaItaly

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