Hyperforin

Hyperforin is one of the principal constituents identified in St John's wort. Hyperforin is a prenylated phloroglucinol believed to be the main active constituent responsible for its antidepressant effects. (Barnes et al., 2002) Hyperforin has been shown to inhibit the uptake of 5-HT(serotonin), dopamine, noradrenaline, GABA and glutamate. (Chatterjee et al., 1998) Hyperforin is also thought to be responsible for the induction of the cytochrome P450 enzymes CYP3A4 and CYP2C9 by binding to the Pregnane X Receptor (PXR).

As ejaculatory control
Hyperforin and other serotonin agonists significantly reduces the pelvic floor contractions elicited by 8-OH-DPAT. Thus, pharmacological modulation of the ejaculatory threshold using serotonin reuptake inhibitors and hyperforin may offer patients an option of achieving improved ejaculatory control.