title: Hypericin levels in human serum and interstitial skin blister fluid after oral single-dose and steady-state administration of Hypericum perforatum extract (St. John's wort).
abstract: The photodynamically active plant pigment hypericin, a characteristic metabolite of Hypericum perforatum (St. John's wort), is widely used as an antidepressant. When administered orally, phototoxic symptoms may limit the therapeutic use of hypericin-containing drugs. Here we describe the high-performance liquid chromatographic (HPLC) detection of hypericin and semiquantitative detection of pseudohypericin in human serum and skin blister fluid after oral single-dose (1 x 6 tablets) or steady-state (3 x 1 tablet/day, for 7 days) administration of the Hypericum extract LI 160 in healthy volunteers (n = 12). Serum levels of hypericin and pseudohypericin were always significantly higher than skin levels (p </= 0.01). After oral single-dose administration of Hypericum extract the mean serum level of total hypericin (hypericin + pseudohypericin) was 43 ng/ml and the mean skin blister fluid level was 5.3 ng/ml. After steady-state administration the mean serum level of total hypericin was 12.5 ng/ml and the mean skin blister fluid level was 2.8 ng/ml. These skin levels are far below hypericin skin levels that are estimated to be phototoxic (>100 ng/ml).
authors.affiliation: Department of Dermatology, University of Freiburg, Germany. schempp@hau1.ukl.uni-freiburg.de
authors.forename: C M
authors.initials: CM
authors.lastname: Schempp
authors.forename: B
authors.initials: B
authors.lastname: Winghofer
authors.forename: M
authors.initials: M
authors.lastname: Langheinrich
authors.forename: E
authors.initials: E
authors.lastname: Schöpf
authors.forename: J C
authors.initials: JC
authors.lastname: Simon
mesh_terms: D000328:Adult; D000873:Anthracenes; D000928:Antidepressive Agents / Q000097:blood / Q000493:pharmacokinetics*; D001768:Blister / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D020448:Ericales; D006801:Humans; D010569:Perylene / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D010936:Plant Extracts / Q000493:pharmacokinetics; D012867:Skin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D000873:Anthracenes; D000928:Antidepressive Agents; D010936:Plant Extracts; D010569:Perylene; C004965:hypericin; C056602:pseudohypericin