St. John's Wort: study protocols
21 study groups say how much St. John's Wort participants took a day. These are the doses the studies gave. They are not a recommendation.
Dose per serving from products
232 products in our catalogue print how much St. John's Wort a serving holds.
Most common: 100 mg to 250 mg, 47% of 232 products.
| Dose per serving | Products |
|---|---|
| 25 mg or less | 10 |
| 25 mg to 50 mg | 24 |
| 50 mg to 100 mg | 19 |
| 100 mg to 250 mg | 108 |
| 250 mg to 500 mg | 38 |
| 500 mg to 1 g | 30 |
| over 1 g | 3 |
Dose per serving from research
21 study groups in 10 studies say how much St. John's Wort participants took a day.
These are the doses the studies gave. They are not a recommendation.
Most common: 500 mg to 1 g, 48% of 21 study groups.
| Daily dose | Study groups |
|---|---|
| 250 mcg or less | 1 |
| 250 mcg to 500 mcg | 1 |
| 500 mcg to 1 mg | 1 |
| 1 mg to 2.5 mg | 0 |
| 2.5 mg to 5 mg | 0 |
| 5 mg to 10 mg | 0 |
| 10 mg to 25 mg | 0 |
| 25 mg to 50 mg | 1 |
| 50 mg to 100 mg | 0 |
| 100 mg to 250 mg | 0 |
| 250 mg to 500 mg | 1 |
| 500 mg to 1 g | 10 |
| 1 g to 2.5 g | 3 |
| 2.5 g to 5 g | 3 |
Commonly used together
None of these 21 study groups took St. John's Wort with anything else.
21 study groups