I have been extremely unconfortable with Lactulose by the end of the day of my test.I only specululate that my test are positive but i can't imagine 4 weeks on it.Glucose give bloat but Lactulose give twice the bloat.Weird enough,at first i felt fine but when Lactulose reach the lower bowel,it get stuck.NO LAXATIVE action from Lactulose from my bowel view.Flux,i think it help the motility of the upper tract but it slows down the colon.