Clinical Drug Investigation

, Volume 22, Supplement 1, pp 7–14 | Cite as

Efficacy of L-Carnitine in Reducing Hyperammonaemia and Improving Neuropsychological Test Performance in Patients with Hepatic Cirrhosis

Results of a Randomised Trial
  • Angelo Cecere
  • Francesco Ciaramella
  • Luciano Tancredi
  • Ciro Romano
  • Adriano Gattoni
Original Research Article


Objectives:To determine the efficacy of L-carnitine in reducing hyperammonaemia and improving neuropsychological performance in patients with hepatic cirrhosis and subclinical hepatic encephalopathy (SHE).

Design: Randomised, parallel group, controlled trial.

Patients and Methods: The study enrolled 31 patients with hepatic cirrhosis resulting from hepatitis C and/or hepatitis B, alcohol abuse and other causes. Patients randomised to active treatment, received oral L-carnitine 6 g/day in two divided doses for 4 weeks. Diagnosis of SHE was based on psychometric tests (subtests of the Wechsler Adult Intelligence Scale-Revised and the Halstead-Reitan Neuropsychological Test Battery) carried out at beginning and end of study. Serum ammonia levels were measured before treatment and weekly thereafter.

Results: A total of 27 patients completed the study. Sixteen patients received L-carnitine and 11 served as controls (no treatment). L-carnitine caused rapid and significant reductions in ammonia levels, sustained over the 4-week treatment period (mean reductions 60.1 and 1.4 (μmol/L in the treated and control groups, respectively). Normal ammonia levels were attained in 14 of 16 patients receiving L-carnitine. Based on psychometric test results, seven patients (43.7%) in the L-carnitine group and five (45.5%) in the control group had SHE at baseline. L-carnitine treatment for 4 weeks caused a net overall improvement in psychometric test results compared with controls. No clinically significant adverse events were reported and all patients receiving L-carnitine reported subjective improvements in their condition.

Conclusions: Results of this preliminary study indicate that L-carnitine reduces hyperammonaemia and improves the clinical symptoms of SHE in patients with hepatic cirrhosis.


Carnitine Hepatic Encephalopathy Ammonia Level Psychometric Test Hepatic Cirrhosis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We would like to thank Dr Antonio Vetrano for his expert help and advice in performing statistical analyses and Sigma-Tau for supplying L-carnitine.


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Copyright information

© Adis International Limited 2002

Authors and Affiliations

  • Angelo Cecere
    • 1
  • Francesco Ciaramella
    • 1
  • Luciano Tancredi
    • 1
  • Ciro Romano
    • 1
  • Adriano Gattoni
    • 1
  1. 1.Department of Clinical and Experimental Medicine ‘F.Magrassi’II University of NaplesNaplesItaly

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