Mood Support
St. John's Wort
Also known as: Hypericum perforatum, Hypericum, St. John's Wort (Menopause Mood), Hypericin
St. John's Wort is a traditional herbal supplement used primarily for mood support, with moderate clinical evidence supporting its efficacy for mild-to-moderate depressive symptoms comparable to some conventional antidepressants. However, it carries significant drug-herb interaction risks and variable standardization across commercial products.
Primary uses
- Mild depression
- Mood support
- Seasonal affective disorder
- Menopause mood
- Mild-moderate depression
- Anxiety (menopause)
- Mild-to-moderate depressive symptoms
- Emotional wellness
- Stress response
How it works
- Contains hypericin and hyperforin
- MAO inhibition and serotonin effects
- Multiple mechanisms
Dosage
- Typical range
- 300mg 3x daily (standardized)
- Timing
- With meals, divided
- With food
- Yes
- Duration
- 4-6 weeks for effect
- Special populations
- Mild depression, SAD
Forms
- Capsule
- Standardized extract
- Perika, Kira
- Powder extract· 70/100
- Tablet· 70/100
- Liquid extract· 70/100
- Tincture· 70/100
Safety
Common side effects
- Photosensitivity
- GI upset
- Fatigue
- Dry mouth
Contraindications
- Transplant patients (cyclosporine, tacrolimus)
- HIV/AIDS patients on antiretroviral therapy
- Cancer patients on chemotherapy
- Patients on SSRIs, SNRIs, or MAOIs
- Patients on warfarin or anticoagulants
- Women using hormonal contraceptives
- Bipolar disorder (may trigger mania)
- Pregnancy and breastfeeding
Known interactions
- Dangerwith SSRI
Combining St John's wort with any SSRI risks serotonin syndrome — a potentially fatal hyperserotonergic state.
- Dangerwith birth control
St John's wort reduces oral contraceptive effectiveness and has caused breakthrough bleeding and unintended pregnancies.
- Dangerwith cyclosporine
St John's wort substantially lowers cyclosporine levels and has caused documented transplant rejection.
Evidence notes
Strong evidence for mild-moderate depression
Grade A: Multiple well-designed human trials support the main claims.
Cited research for St. John's Wort
Clinical studies referenced across Formulate guides that mention st. john's wort. Each links to the full study page with PubMed source + the guides that cite it.
- Primary literature (2024)Systematic review
Co-administration of St. John's wort and hormonal contraceptives: a systematic review
- Primary literature (2024)Monograph
St. John's Wort — StatPearls
- Rigotti et al. (2020)J Food Biochem
Clinical relevance of St John's wort drug interactions revisited
- Acosta-Rodriguez et al. (2007)Nat Immunol
St John's wort (Hypericum perforatum): drug interactions and clinical outcomes
- Evans et al. (2003)Anaesthesia
Interaction of St John's wort with low-dose oral contraceptive therapy: a randomized controlled trial
- Moschella et al. (2001)Am J Kidney Dis
Interaction between cyclosporine and Hypericum perforatum (St John's wort) after organ transplantation
- Ruschitzka et al. (2000)Lancet
Acute heart transplant rejection due to Saint John's wort
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