Investigation of pharmacokinetic data of Hypericin, Pseudohypericin, Hyperforin and the Flavonoids Quercetin and Isorhamnetin revealed from single and multiple oral dose studies with a hypericum extract containing tablet in healthy male volunteers - Schulz, H U; Schürer, M; Bässler, D; Weiser, D (Arneim./Forsch/Drug Res, 2005)