Brooke Mueller Refuses Drug Test

Charlie Sheen's ex wife on the verge of losing her sons for refusing a drug test.

Brooke Mueller just refused to submit to a drug test ... TMZ has learned.

As we have been reporting, multiple sources tell us Brooke has fallen off the wagon and has been out of control over the last few days. We posted a surveillance video from an Inglewood pawn shop yesterday showing a very jumpy Brooke trying to pawn a watch and a stereo.

Under her custody settlement agreement with Charlie Sheen, Brooke is required to submit to drug testing. A test was scheduled for 6 PM PDT today. We're told the people conducting the test came to her home but Brooke's lawyer -- Ron Rale -- who was present, told them she would not take the test.

Under the settlement, a refusal is considered a dirty test.

It's unclear what Charlie and his lawyer will do now.

Jacked from TMZ