Acceleration of the gastrointestinal transit by polyethylene glycol effectively treats unconjugated hyperbilirubinaemia in Gunn rats

Background and aimsSeveral conditions that delay gastrointestinal transit are associated with unconjugated hyperbilirubinaemia. We hypothesised that the gastrointestinal transit time is directly related to plasma unconjugated bilirubin (UCB) concentrations, and that this relationship can be used to develop a new therapeutic strategy for severe unconjugated hyperbilirubinaemia in the Gunn rat model.MethodsGunn rats received, for various time periods, oral polyethylene glycol (PEG) with or without conventional phototherapy treatment to accelerate, or oral loperamide to delay gastrointestinal transit. Gastrointestinal transit time and UCB concentrations in plasma, faeces, intestinal content and bile were determined.ResultsWithin 36 h, PEG administration accelerated gastrointestinal transit by 45% and simultaneously decreased plasma UCB concentrations by 23% (each p