Time course of total (free and conjugated) plasma concentrations of catechin, caffeic acid, ferulic acid and U10. These compounds revealed an early tmax (time of maximal plasma concentration) up to five hours after intake of the pine bark extract. Symbols represent time course of mean and standard deviation of concentrations after a single dose of 300 mg Pycnogenol. The columns represents mean and standard deviation of concentrations after repeated doses of 200 mg Pycnogenol daily after five days (assumed steady state). Steady state concentrations of U10 were detectable in only two volunteers and are not shown in this diagram.