Lactulose is used in hepatic encephalopathy to achieve which effect?

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Multiple Choice

Lactulose is used in hepatic encephalopathy to achieve which effect?

Lactulose works by lowering the colonic pH to trap ammonia in the gut and reduce its absorption. When lactulose is fermented by colonic bacteria, it produces acids that acidify the lumen. This acidic environment shifts the ammonia balance from ammonia (NH3) to ammonium (NH4+), a charged form that cannot cross the gut wall easily. As a result, less ammonia enters the portal circulation and more is excreted in stool. The laxative effect of lactulose also speeds stool transit, which helps remove ammonia-containing material faster. It doesn’t directly inhibit ammonia production or increase hepatic clearance, and it isn’t a sedative.

Lactulose works by lowering the colonic pH to trap ammonia in the gut and reduce its absorption. When lactulose is fermented by colonic bacteria, it produces acids that acidify the lumen. This acidic environment shifts the ammonia balance from ammonia (NH3) to ammonium (NH4+), a charged form that cannot cross the gut wall easily. As a result, less ammonia enters the portal circulation and more is excreted in stool. The laxative effect of lactulose also speeds stool transit, which helps remove ammonia-containing material faster. It doesn’t directly inhibit ammonia production or increase hepatic clearance, and it isn’t a sedative.

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