psylocibe mushrooms are not tested for in standard drug tests, but it is possible (but difficult and apparently expensive) to test for them.
check out www.erowid.com for info on this and many other exciting drug tests.
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"Sometimes not knowing everything's the only thing that makes it okay." - Delerium, The Sandman
JustStark, Grand High Pubah of subhuman affairs and official corner- office holder of the ANTI-TRIAD