From the Guidelines
St. John's Wort (Hypericum perforatum) is a flowering plant with medicinal properties that has been used for centuries as a natural remedy, primarily known for its antidepressant effects. It is commonly used to treat mild to moderate depression, with effectiveness comparable to some prescription antidepressants for these cases. The typical dosage for depression is 300 mg of standardized extract (containing 0.3% hypericin) taken three times daily for 4-6 weeks before evaluating effectiveness, as seen in studies such as 1. St. John's Wort works by inhibiting the reuptake of neurotransmitters like serotonin, dopamine, and norepinephrine in the brain, similar to how conventional antidepressants function. However, it's crucial to be aware that this herb can interact with many medications, including birth control pills, blood thinners, heart medications, and other antidepressants, potentially reducing their effectiveness or causing adverse effects, as noted in 1 and 1. Some key points to consider include:
- St. John's Wort may decrease platelet aggregation and has a high risk of interacting with other medications, particularly those that are metabolized by the liver enzyme CYP3A4, as indicated in 1.
- The herb can cause side effects like sensitivity to sunlight, dry mouth, dizziness, digestive issues, and anxiety.
- Anyone considering St. John's Wort should consult with a healthcare provider before starting it, especially if taking other medications or having existing health conditions.
- Recent studies, such as 1, highlight the importance of monitoring potential interactions between St. John's Wort and other medications, such as warfarin, to minimize risks. Given the potential benefits and risks, it is essential to approach the use of St. John's Wort with caution and under the guidance of a healthcare professional, as emphasized in various studies, including 1, 1, 1, 1, 1, and 1.
From the Research
What is St. John's Wort?
St. John's Wort, also known as Hypericum perforatum, is a herbal remedy that has been used for centuries to treat various health conditions, including depression.
Uses and Efficacy
- It is effective in treating mild-to-moderate depression, with a response rate of 60-70% estimated by analysis of pooled data 2.
- St. John's Wort has comparable efficacy and safety when compared to selective serotonin reuptake inhibitors (SSRIs) in patients with mild-to-moderate depression 3, 4.
- It has been shown to have a significant clinical efficacy in ameliorating depressive symptoms, with a pooled standardized mean difference (SMD) from baseline Hamilton Rating Scale for Depression (HAM-D) scores of -0.068 3.
Safety and Interactions
- St. John's Wort can interact with various prescription drugs, including alprazolam, amitriptyline, cyclosporine, digoxin, and warfarin, by lowering their plasma concentrations 5, 6.
- It can cause serotonergic syndrome when combined with serotonin reuptake inhibitors, such as sertaline and paroxetine 5, 6.
- St. John's Wort has been shown to decrease the plasma concentration of oral contraceptives, leading to breakthrough bleeding and unplanned pregnancies 6.
Tolerability and Side Effects
- St. John's Wort preparations are generally well-tolerated, with rare adverse drug reactions, mainly subjective symptoms such as gastrointestinal issues and dizziness 2.
- The use of St. John's Wort has a lower discontinuation/dropout rate compared to standard SSRIs 3.
- It has a good tolerability profile in elderly patients 2.