Old thread is Old, strawdog. And although it's not technically/chemically an opioid, it is most assuredly an opioid-agonist drug. In other words, it affects the opioid receptors as if it were. Which means for all intents and purposes AFA your brain is concerned ... it's an opioid.
The answer to the OP was that's probably only detectable for about 3 days, and that's if they're doing like a thorough urinalysis test. With cheaper tests, it probably wouldn't even be detected if you were ON it when you took the test because they wouldn't screen for it. Probably a lot longer w/a hair test though.