Enhanced absorption of oral furosemide by bile juice in rats.

The effect of bile juice on gastrointestinal absorption of furosemide was investigated in rats. Furosemide intravenous solution (Lasix), 20 mg/kg, was administered orally with (n = 5) or without (n = 6) bile juice administration after bile duct cannulation. With bile juice administration, the plasma concentrations of furosemide were considerably higher and AUC(0-8) h was significantly greater (2570 versus 658 microg x min/ml) suggesting that absorption of furosemide increased significantly by bile juice. This was supported by significantly smaller in the percentages of oral dose of furosemide recovered from entire gastrointestinal tract at 24 h: the values were 29.5% and 58.0% with and without bile juice administration, respectively.