Usually it tests for Pot, Cocaine, Benzo's (xanax, valuim), and opiates (pain killers, OC's, lortabs, oxycodone, etc.). Some places (depending on if it is a misd. Or felony probation) can test for alcohol, PCP and ecstacy as well.
What Kind Of Drug Test Do Probation Have.?
Most probation drug screens are 10 panel, which basically tests for everything.