Editor—Als-Nielsen et al systematically reviewed randomised trials using lactulose or lactilol for hepatic encephalopathy,1 which has been warranted for some time. We agree that non-absorbable disaccharides have been introduced into clinical practice without any convincing evidence base but question the authors' conclusion, that there is insufficient evidence to determine whether non-absorbable disaccharides are of benefit to patients with hepatic encephalopathy. Surely, this comprehensive review shows clearly that lactulose is ineffective for treatment of hepatic encephalopathy, rather than there being insufficient evidence.
Furthermore, the results of this study have several important implications.
Firstly, what should comprise standard medical treatment for hepatic encephalopathy? Lactulose should no longer be included, but strict attention should be paid to treating the precipitating factors, with correction of dehydration, electrolyte and acid base imbalance,2 constipation, and infection.3
Secondly, we make a plea for placebo controlled trials: no restriction should be imposed on the conduct of placebo controlled studies on ethical grounds.
Thirdly, the interorgan metabolism of ammonia should be revisited and the recent studies showing the important roles of the small intestine, muscle, and kidneys in regulating the blood concentrations of ammonia considered.4
Competing interests: None declared.
References
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