St. John's Wort may reduce melatonin effectiveness by increasing its metabolism.
St. John's Wort induces CYP enzymes that metabolize melatonin more quickly.
You may need a higher melatonin dose if taking St. John's Wort. Consider alternative sleep supplements.
Known drug category interactions for these supplements. Especially relevant if you take prescription medications.
Combining St. John's Wort with SSRIs can cause serotonin syndrome, a potentially life-threatening condition.
NEVER combine St. John's Wort with SSRIs, SNRIs, or MAOIs. Wait at least 2 weeks after stopping an SSRI before starting St. John's Wort.
St. John's Wort reduces the effectiveness of hormonal birth control, potentially causing contraceptive failure.
Use a non-hormonal backup contraceptive method while taking St. John's Wort and for one month after stopping.
St. John's Wort significantly reduces warfarin blood levels, potentially causing blood clots.
Do not take St. John's Wort while on warfarin. If already taking both, do not stop St. John's Wort abruptly — consult your doctor.
Melatonin may affect blood pressure and interact with some antihypertensive drugs.
Monitor blood pressure if combining. Some people experience higher blood pressure with melatonin — effects vary.