The bond between hormonal fluctuations and depression is inextricable. Estrogen is a feel-good drug, and when levels lag (either at the end of the cycle or during perimenopause), the dark clouds roll in. Lucky for us, St. John's Wort has a long history of combating mild to moderate depression, and the perks likely extend to estrogen-related blues. Studies have found that 900 to 1,200 mg of St. John’s Wort a day can be just as effective in treating mild to moderate depression as tricyclic antidepressants and SSRIs, but without side effects like weight gain, decreased sex drive, fatigue, and insomnia. In one small trial, St. John's Wort reduced PMS symptoms by 50 percent.