Amongst St. John's Wort's active ingredients there is one in particular which has received a great deal of attention and this is a substance called Hypericin. St. John's Wort is standardised to ensure the same level of hypericin (1000mcg) in each tablet. Most other one-a-day products supply just 900mcg hypericin! Please check with your doctor or pharmacist if you are taking any prescribed medicines as St John's Wort may affect the way they work. Do not take if pregnant or breast feeding. Recommended daily intake: 1 tablet