Holy sh**........milk thistle inhibits testosterone (and rather big league-ly too). 
Time- and Concentration-Dependent Inactivation of Testosterone Metabolism of P450 3A4 by Silybin. 6 -Hydroxytestosterone was the major metabolite detected when testosterone was incubated with purified recombinant P450 3A4 in a reconstituted system in the presence of NADPH. Silybin inhibited the metabolism of testosterone by P450 3A4 in a time-, concentration-, and NADPH-dependent manner.
http://dmd.aspetjournals.org/content/dmd/32/6/587.full.pdf
Time- and Concentration-Dependent Inactivation of Testosterone Metabolism of P450 3A4 by Silybin. 6 -Hydroxytestosterone was the major metabolite detected when testosterone was incubated with purified recombinant P450 3A4 in a reconstituted system in the presence of NADPH. Silybin inhibited the metabolism of testosterone by P450 3A4 in a time-, concentration-, and NADPH-dependent manner.
http://dmd.aspetjournals.org/content/dmd/32/6/587.full.pdf
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