One low-hyperforin extract moved no drug level, in 20 people
Given with a cocktail of probe drugs covering six clearance pathways, every result came back inside the range that counts as no interaction. It left digoxin untouched too.
What the study found
One extract, bred low in hyperforin, moved no drug level at all
A deliberately low-hyperforin extract was given with a cocktail of probe drugs covering six major clearance pathways, and every one came back inside the range that counts as no interaction. An independent trial found the same extract left digoxin untouched.
The caveat · Run by its maker, not randomised
Five of the eight authors work for the company that makes the extract and two more for the contract research organisation that ran the study. The design was open-label, non-randomised and single-sequence, in 20 people. The result belongs to this one proprietary extract, not to St John's Wort products in general, most of which carry far more hyperforin.
What we don't know
Five of the eight authors work for the company that makes the extract and two more for the contract research organisation that ran the study. The design was open-label, non-randomised and single-sequence, in 20 people. The result belongs to this one proprietary extract, not to St John's Wort products in general, most of which carry far more hyperforin.