From the Guidelines
Hydrocodone will not typically test positive for oxycodone on a urine drug screen (UDS) because modern immunoassay tests are designed to distinguish between these different opioid compounds. These are different opioid medications that are detected separately on most standard drug tests. Hydrocodone is metabolized to hydromorphone in the body, while oxycodone is metabolized to oxymorphone 1. If you are prescribed hydrocodone and are being tested for medication compliance, it will show up as positive for hydrocodone/hydromorphone but negative for oxycodone/oxymorphone. This distinction occurs because these medications have different chemical structures despite both being opioid pain relievers.
Some key points to consider:
- Standard urine tests for opiates can detect morphine and codeine, but not synthetic opioids such as oxycodone and hydrocodone 1.
- Providers should confirm which substances are included in the panel before administration of the screening 1.
- A negative ECPO screen does not mean that individuals are not engaged in ECPO use, and providers should be aware of this limitation 1.
- It's essential to inform the testing facility about all medications you're currently taking to avoid any potential issues with drug testing results 1.
In terms of clinical practice, it's crucial to use the most recent and highest-quality evidence to guide decision-making, and in this case, the evidence suggests that hydrocodone and oxycodone are distinct opioid compounds that can be detected separately on most standard drug tests 1.
From the Research
Urine Drug Screening for Hydrocodone and Oxycodone
- Hydrocodone may be detected in urine drug screens (UDS) for patients taking oxycodone due to the presence of hydrocodone as an impurity in oxycodone preparations 2.
- The frequency and concentration of hydrocodone in UDS specimens are related to the concentration of oxycodone, with higher concentrations of oxycodone resulting in higher frequencies of hydrocodone detection 2.
- When oxycodone concentrations are > 100,000 ng/ml, hydrocodone should be < 1500 ng/ml, and when oxycodone concentrations are < 100,000 ng/ml, hydrocodone should be < 500 ng/ml; values greater than these indicate non-prescribed hydrocodone use 2.
Cross-Reactivity in Urine Drug Screening Immunoassays
- Urine drug screening immunoassays can cross-react with unrelated compounds, leading to false-positive results 3.
- A systematic approach to discovering cross-reactive substances using electronic health records (EHRs) can help identify potential cross-reactivities and improve the interpretation of UDS results 3.
Metabolites in Urine Drug Testing
- Normetabolites such as norcodeine, norhydrocodone, and noroxycodone can be used to facilitate interpretation and reduce false negatives in urine drug testing for semi-synthetic opiates 4.
- The detection of normetabolites in urine specimens can provide conclusive evidence of parent drug consumption 4.
GC-MS Confirmation of Opiates in Urine
- Gas chromatography-mass spectrometry (GC-MS) can be used to confirm the presence of codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone in urine specimens 5, 6.
- GC-MS analysis of trimethylsilyl (TMS) ether derivatives and methoxime (MO)-TMS derivatives can distinguish among eight opiate drugs in urine, including hydrocodone and oxycodone 6.