DrugBuyers.Com: Percocet????Oxycodone???

It depends on the specific test, but hydrocodone and oxycodone can cross-react with many opiate tests.

From many online resources...

"A qualitative urine test for opiates is performed in suspected overdose cases or as part of a drug of abuse program. The test is most sensitive for morphine and codeine but other drugs will cross react in an immunoassay and give positive results (eg, hydrocodone, hydromorphone)."

"An opiate confirmation was performed to a testing limit of 50 ng/mL for total morphine and codeine. In addition, hydrocodone and hydromorphone were qualitatively identified."

"A drug is detected by the screening device, but it wasn't one of the drugs detected in the confirmation analysis. An example of this is the drug hydrocodone which is found in Vicodin. Hydrocodone is a member of the opiate family and a urine sample containing enough hydrocodone will trigger the DTN Home Drug Test to indicate an "inconclusive" result. Unfortunately, the confirmation test is specific only for codeine and morphine. So the urine containing hydrocodone will be resulted by the laboratory as a "negative" sample."

"Cross-Reactivity
A study was conducted using morphine-related compounds to determine the cross-reactivity of the test.

Morphine structurally related compounds showing the lowest concentration of the drug producing a positive response equivalent to the cutoff level:
Description Concentration (ng/ml)
Morphine 300
Codeine 300
Ethyl Morphine 300
Hydromorphine 400
Hydrocodone 750
Oxycodone 1000 "
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Again, it completely depends on the test.

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