St.John`s Wort contains the following compounds Naphthodianthrones (protohypericin, protopseudohypericin, hypericin and cyclopseudohypericin), flovonoids(quercetin, rutin and luteolin),tannins, several amino acids, and hyperforin. Hypericin and its related components are said to be responsible for St.John`s wort benefit on mood. Studies also shows that Hypericum extract LI 160 causes 50% inhibition of serotonin uptake., it also suppresses release of interleukin-6 , can decrease cell surface 5-hydroxytryptamine (5HT) receptors. St. John`s wort extract can inhibit binding at muscarinic cholinergic receptor, norepinephrine uptake sites, 5-hydroxytryptamine (5HT) and this is only at high concentration. Furthermore, hyericin and pseudohypericin
