Does folinic acid have a choleretic effect on humans?

The aim of this study was to clarify whether folinic acid has any choleretic effect in humans, as observed by Kajiyama et al. in both clinical and experimental studies. The choleretic effect of folinic acid was analyzed prospectively in a subgroup of patients who had external biliary catheters with periampullary tumors causing complete biliary obstruction. Folinic acid (50mg/day) was administered twice with a 24-hour interval between each dose. Daily bile volume was then recorded on the three consecutive days following the first dose of folinic acid. Mean bile flows (basal output=mean bile volume of four days) before and after (fifth, sixth and seventh days) the initiation of folinic acid administration were then compared. Mean bile volumes were determined as baseline output: 669.20+/-235.18, 5th day=: 668.63+/-235.26, sixth day: 670.45+/-235.08, and seventh day: 670.00+/-235.11. No significant difference in daily bile volumes before and after folinic acid administration was detected (p>0.05). No choleretic effect of intravenous folinic acid administration was observed in this prospective clinical study. This finding was contrary to our previous study on this subject.