It came to light on Saturday that Chael Sonnen , who tested positive for prohibited substances at a May 24 random drug test in Las Vegas, had also tested positive for prohibited substances stemming from a second random test on June 5 in Portland, Ore. The May 24 test showed that Sonnen tested positive for Anastrozole and Clomifene , both of which can be utilized to help treat men with hypogonadism, which Sonnen claims to have.
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UFC Issues Statement on Chael Sonnen’s Positive Drug Test that Includes HGH and EPO – MMA Weekly