Multiple therapeutic modalities have been used to treat hepatic encephalopathy. L: -Acetylcarnitine (LAC) is a physiologically active substance that improves both the energetic and the neurotransmission profiles. LAC is able to cross the hematoencephalic barrier and reach the cerebral regions, where the acetylic group may be utilized. The aim of this work was to evaluate the efficacy of LAC in the treatment of hepatic coma in cirrhotic patients. Twenty-four suitably selected patients were enrolled in the study and, following randomization, received either LAC (n=13) or placebo (n=11). Statistically significant differences in neurological findings, as evaluated by the Glasgow Scale, as well as in ammonia serum levels and BUN were found following LAC treatment. In the placebo group we observed two cases of improved neurological findings as well as one case of improved EEG grading. In the other group we observed an improvement of neurological findings and of EEG grade in 10 and 8 subjects, respectively. Noteworthily, seven (54%) patients went from grade 4 down to grade 3, and one from grade 4 down to grade 1. The improvement in the neurological picture was evident at between 1 and 4 hr after the end of treatment, remaining until 24 hr after. No side effects were observed in our study series. Our study demonstrates that LAC administration improved neurological and biohumoral symptoms in selective cirrhotic patients with hepatic coma.