Human Trial Compares Kratom Extract Exposure With Leaf Powder and Tea

A randomized, double-blind, placebo-controlled trial in healthy adults has characterized how the body handles mitragynine and its metabolite 7-hydroxymitragynine after encapsulated kratom extract, according to a study in the Journal of Analytical Toxicology. Researchers including Marilyn Huestis gave participants single doses, then 15 consecutive daily doses, of a concentrated extract standardized to 39.5% mitragynine.

Plasma levels of both compounds rose within about two hours and increased with dose. The authors reported no or low accumulation of 7-hydroxymitragynine over the multi-day dosing period.

Comparing the results with earlier trials of kratom tea and dried leaf powder, the authors concluded that delivery format influences overall mitragynine exposure, with concentrated extracts potentially producing greater exposure than powder or tea at comparable doses. For a market spanning powders, capsules and extracts, the findings add controlled human data relevant to product-format transparency.