The proposed study will consist of a 9 week double-blind cross-over study trial of milk
thistle in 15 people (ages 18-65). The study will be divided into an initial 4 week phase, a
one week wash out phase, and a second 4 week phase, with one of the 4 week phases consisting
of active treatment with milk thistle, and the other 4 week phase consisting of inactive
placebo treatment. Participants will be randomized to receive either milk thistle or placebo
during the first 4 week phase on a 1:1 basis. This blinding will be maintained by the IDS
pharmacy at the University of Chicago.