SHE'S PLAYING DIRTY! USHER'S EX-WIFE DEMANDS HE TAKE A DRUG TEST!

Usher's ex-wife Tameka Raymond is freaking out that testing the singer for drugs will soon be useless -- because the more time that passes, the more time Usher has to cleanse his system of illicit substances.

In case you haven't been following -- Tameka demanded Usher take a drug test recently because she thinks the singer is popping pills and who-knows-what-else around their kids.

Usher refused on grounds Tameka's demands were "frivolous and unfounded" and only intended to “harass and embarrass” the singer -- but now, Tameka is taking her case back to the judge in the ex-couple's custody war, pleading with the court to force Usher to take the test despite his refusal.

And according to the docs, Tameka wants the court to make it snappy -- claiming, any further delay will allow Usher to "cleanse" any evidence of drugs from his system.

So far, no word back from Usher's reps.Damn! She turned out to be what his MaMa was saying this whole time! She's a Old A$$ Gold Digging B!tch!

SOURCE