St. John's Wort
Half-life
~26-34 hours
What is St. John's Wort?
Medicinal herb with hypericin and hyperforin. FDA-recognized for mood support.
How St. John's Wort works
Hyperforin inhibits reuptake of serotonin, dopamine, and norepinephrine (SNRI-like effect). Hypericin is an MAO inhibitor. Neuroprotective antioxidant.
St. John's Wort half-life
~26-34 hours (hyperforin in plasma)
St. John's Wort side effects
- CYP3A4 inducer — reduces effectiveness of many drugs (birth control, warfarin, statins, etc.)
- Photosensitivity — avoid intense sun exposure
- Contraindicated with SSRIs (serotonin syndrome risk)
- GI upset possible
St. John's Wort interactions
with Birth Control
Avoid · severeSt. John's Wort strongly induces CYP3A4 and P-glycoprotein, dramatically reducing plasma levels of oral contraceptives. Multiple documented cases of unintended pregnancy have resulted from this interaction.
Timing: Do not combine; use additional contraception if SJW is being used
with SSRIs
Avoid · severeSt. John's Wort is a potent serotonin reuptake inhibitor. Combined with SSRIs it dramatically increases risk of serotonin syndrome — a potentially life-threatening condition causing agitation, hyperthermia, and seizures.
Timing: Never combine; allow 2 weeks washout before switching
with Statins
Caution · moderateSt. John's Wort induces CYP3A4 and reduces plasma concentrations of many statins (simvastatin, atorvastatin) by up to 50%, potentially losing cardiovascular protection.
Timing: Avoid combination if possible; if necessary, monitor statin effectiveness closely
Track St. John's Wort in Protokol.
Log doses, model half-lives, check interactions, and line it all up against your bloodwork. Free on iPhone and Android.
