Pharmacokinetics and immunomodulatory effect of lipophilic Echinacea extract formulated in softgel capsules.

An attractive herbal product, softgel capsules containing 10 mg of Echinacea angustifolia lipophilic extract, was given in a single oral administration to 10 human volunteers to perform a pharmacokinetic and immunological study. The plasma concentration of the major constituent was monitored, quantifying at predetermined time points the dodeca-2E,4E,8Z,10E/Z-tetraenoic isobutylamides (tetraene). The plasmatic levels of IL-2, IL-6, IL-8, IL-10 and TNF-a in samples collected before and 24 h after drug administration were analyzed by cytokine assay.