Effects of food on the bioavailability of sustained-release pinacidil in humans.

The effects of a standard breakfast meal on the bioavailability of a sustained-release tablet formulation of pinacidil [(+/-)-2-cyano-1- (4-pyridyl)-3-(1,2,2-trimethylpropyl)guanidine monohydrate) were investigated in eight healthy volunteers. Concomitant food intake resulted in significantly increased maximum measured serum pinacidil concentrations, Cmax, (172 +/- 21 versus 102 +/- 49 ng/mL, p less than 0.05), and relative bioavailability, measured as AUCo-infinity (904 +/- 189 versus 697 +/- 279 ng.h/mL, p less than 0.05). The time to maximum serum concentration (tmax) was not affected by food (2.3 +/- 1.3 versus 3.3 +/- 1.2 h, p greater than 0.05), and the terminal elimination half-life, (t1/2z) was significantly decreased (4.7 +/- 2.2 versus 2.3 +/- 0.4 h, p less than 0.05).