XTC has either meth or herion in it. Typically it will be in a persons system for 72 hours or 3 days. Same as meth.
Crack/cocaine lasts in the human body for 72 hours.
So, if you dont have a PO appt for a couple weeks, hit up the powders.
Otherwise, Whip its, Duster, Spice, Shrooms, Acid...