Effect of guar gum, a fibre preparation, on digoxin and penicillin absorption in man.

The effect of guar gum on the absorption of digoxin and phenoxymethyl penicillin was studied in a double blind study in 10 healthy volunteers. Guar gum reduced serum digoxin concentration during the early absorption period, but a similar amount of digoxin was found in 24 h urine whether given with or without guar gum. Both the peak penicillin concentration and the area under the serum curve were significantly reduced by the gum.