percocet didn't show up in urine test 20 yrs at this clinic NO failed test

[csterg]

I'm perplexed.  I've had 4 back surgeries, permanent nerve damage, torn miniscus in my knee, degenerative disk disease & arthritis in my back/knee/hip etc.  I take  four  325 per day of oxycodone aka percocet.  I've been with my Dr. for 19 years! Today I was told NO medicine at all showed up in my urine.  I've never failed a test in almost 20 years. I switched from methadone to percocet this past year because of a worry with my heart (I'm 53)   They lowered my dose to 2x per day (1/2 of my regular dose) & told me to let them know if I figured out what happened.  I'm just starting to investigate.  any idea what could cause it?  YES I take my medicine! I was in shock & thought they were saying I didn't follow the Drs. orders & didn't take my medicine.  duh they were thinking I was selling it or something!  My hubs makes 6 figures a year so I don't need to "sell" my meds and be in pain! I did have gastric bypass but that was 8 yrs ago, and I do have a dropped bladder.  sigh.  any idea????  I cannot thank you enough for your help!

[backhurtz]

Even with a gastric bypass, because Percocet is immediate release, the bypass should have no impact on the test results.
Was the test an in office screen and/or was the urine test sent out for confirmatory/quantitative testing? If the test was just an in office screen, the threshold levels for detection may have been too high. However if it was sent out for confirmatory/quantitative testing, the Percocet should have turned up, since those tests look specifically for the metabolites of the Percocet and the levels and have a much lower threshold. Do you consume large quantities of water daily? That could cause a flushing out of the Percocet if you drank large quantities of liquids before the test.

[csterg]

TY for helping!  The test is sent off and yes I have a dropped bladder and have frequent urinary tract infections.  I drank tons & tons of water for the 2 days before and took a diuretic. (I have a torn miniscus and it helps with swelling)  I offered to do blood test, lie detector, retest, swab whatever they needed.  Could there have been a mixup or error with the lab? I am taking 1/2 of my usual dose now and can tell a huge difference.  I have an 11 year old and I have to figure this out.    I have to be mobile.  I'm miserable ty for your help.  

[backhurtz]

Unfortunately, given you said you drank large amounts of water and took a diuretic before the test, you likely flushed the Percocet from your system. Cranberry juice or even cranberry supplements are usually helpful in preventing bladder infections, far more than drinking large quantities of water.  Have you been notified of the results of the test results of the urine test ? It likely showed little to no amount of Percocet from the flushing of water and diuretic combo. There really isn’t much you can do at this point, other than to not consume mega amounts of water in the days before your appt, in the event you are tested again, and take the meds exactly as prescribed. I would avoid the diuretic as well in the week leading up to an appt.