A Second Hepatic Encephalopathy Admission: Add Rifaximin or Fix the Lactulose First
A patient's second hepatic encephalopathy admission on lactulose alone raises the option of adding rifaximin. Before the team agrees on that, someone has to establish whether the lactulose he's been sent home on was ever actually working at the dose he was taking it.
Harold P., a 69-year-old man, spent his career as a high school shop teacher and still keeps a small woodworking bench in his garage, though his daughter has quietly started hiding the power tools since his first hepatic encephalopathy episode eight months ago. He has cirrhosis from longstanding hepatitis C, cured with direct-acting antivirals four years ago but left with decompensated liver disease. He was discharged after that first episode on lactulose, titrated at the time to two to three soft bowel movements daily, and has now been readmitted with recurrent confusion and asterixis, his second HE episode in eight months. His MELD score is 15, unchanged from his last admission, and he has no identifiable precipitant this time — no infection, no GI bleed, no new sedating medication.
What isn't yet clear is whether the lactulose he's been taking at home actually reflects that discharge titration. When directly asked, he reports one, sometimes two bowel movements a day, well short of his own target range, and admits he's been inconsistent with the dose because of how disruptive frequent bathroom trips are to sleeping through the night. A second HE admission is real evidence something needs to change — but whether that means his current drug has failed, or was never actually given a fair trial at the dose it requires, is the question the team is working through before deciding what, if anything, to add.
What a second admission is actually evidence of
I'd add rifaximin today. Bass's randomized trial of rifaximin added to lactulose enrolled exactly his situation — already on lactulose, still recurring — and showed real reductions in both breakthrough episodes and HE-related hospitalization over lactulose alone. Two admissions in eight months is enough evidence of risk that I don't want to wait through another cycle to see if something else was the problem.
Before we credit lactulose with having failed, I'd want to actually establish that it was given a fair trial. He's reporting one to two bowel movements a day against a target of two to three, and he's told us directly why — the frequency was disruptive enough that he cut back on his own. That's not lactulose not working; that's lactulose not being taken at an adequate dose, which is a different problem with a different fix.
Calling for combination therapy on the strength of 'he's already on lactulose' assumes the lactulose he's on is the lactulose the trials tested against — and by his own report, it isn't.
I don't think these positions are actually in conflict once you look at what he's already been through. Retitrate the lactulose to his real target starting today — that part isn't optional regardless of what else we do. But I'd add rifaximin at the same visit rather than waiting to see if fixing the lactulose alone would have been enough. He's had two admissions; asking him to tolerate a third while we run that experiment isn't the cautious choice, it's just a different kind of risk.
Both changes made at the same admission: lactulose retitrated with direct patient teaching, rifaximin added rather than held for a future admission.
Discharge plan included a specific home bowel-movement log, at the primary care physician's suggestion, so the next visit can actually confirm whether the lactulose dose is being reached this time rather than relying on recall alone.