Background and Aims: Lactulose is the first-line drug for both treatment and secondary prophylaxis for overt hepatic encephalopathy (HE). The use of lactulose for the primary prophylaxis of HE in patients with cirrhosis and acute upper gastrointestinal bleeding (AUGIB) has been debated. Hence, we conducted this meta-analysis to assess the role of lactulose in HE prophylaxis in patients with cirrhosis and AUGIB.

Methods: A comprehensive search of literature from inception to December 2022 was performed of three databases for randomized studies comparing lactulose and placebo in patients with cirrhosis and AUGIB. Risk ratios (RR) with 95% confidence intervals were calculated for all the dichotomous outcomes.

Results: A total of five studies were included in the final analysis, out of which three studies had a low risk of bias, and two had a moderate risk of bias. Lactulose therapy was associated with a significantly lower risk of OHE compared to placebo, with a RR of 0.38 (0.23-0.62) and a number needed to treat of 6. There was no difference in the risk of mortality between the groups, with a RR of 0.71 (0.29-1.76). The pooled incidence rates of overall adverse events (AEs) and diarrhea with the use of lactulose therapy were 53.2% (42.2- 64.2) and 34.7% (17.7-51.7), but a majority did not require drug discontinuation. The certainty of the evidence was moderate to low.

Conclusions: Prophylactic lactulose reduces the incidence of HE after AUGIB but has no effect on mortality. Diarrhea and abdominal discomfort are common AEs but do not need drug discontinuation.


variceal bleeding, gastrointestinal bleeding, cirrhosis, hepatic encephalopathy, lactulose