Anderson Silva failed second drug test administered by Nevada State Athletic Commission (NSAC) following victory vs. Nick Diaz on Jan. 31 at UFC 183. Silva tested positive in post-fight urine test for steroid drostanolone, same banned substance found in system during out-of-competition test Jan. 9, as well as anti-anxiety medication Oxazepam and Temazepam, which is used to treat sleep deprivation.
Source: Fox sports 1
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