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Oxymorphone/Creatinine Ratio, Urine — Body-Mass Adjusted Mass Concentration

Published: August 9, 2026Updated: August 16, 2026

A urine test that measures oxymorphone relative to creatinine and may account for body mass, helping evaluate recent opioid exposure.

Quick summary

["This test can help determine whether oxymorphone, an opioid-related substance, is present in the urine."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
78765-5
Short code
oxyMORphone adj bodymass+crea Ur-mCnc
Synonyms
oxyMORphone adj bodymass+crea Ur-mCnc
Category
kidney
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

This test measures oxymorphone in urine compared with urine creatinine, with the result potentially adjusted for body mass. Oxymorphone is an opioid-related substance and can be present after use of certain prescription opioids or illicit opioids.

Why might I need this test?

This test may be used for medication monitoring, drug screening, or investigation of suspected opioid use. It is often interpreted together with the clinical history and other urine drug tests.

How is the test performed?

A urine sample is analyzed in the laboratory to determine the amount of oxymorphone relative to creatinine. The creatinine comparison helps account for differences in urine concentration.

How do I prepare for the test?

Follow the collection instructions provided by the laboratory or clinician. Tell the clinician about any prescription opioids, other medicines, supplements, and supplements or substances that may affect the result; do not stop prescribed medication without medical advice.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Detecting oxymorphone may indicate recent exposure to an opioid such as oxycodone or another opioid that produces oxymorphone. The result alone cannot identify the exact medication or dose, because timing, metabolism, urine concentration, and individual differences affect the measurement.

Short name

Urine oxymorphone/creatinine

Frequently asked questions

Does this test show how much opioid I took?
No. It can show that oxymorphone was detected and may support assessment of recent exposure, but it cannot reliably determine the exact dose or time of use.
Why is creatinine included?
Creatinine helps normalize the urine result because urine can be more or less concentrated. A body-mass adjustment may also be used when appropriate for the patient.
Can prescribed medication cause a positive result?
Yes. Certain prescription opioids, including oxycodone, can produce oxymorphone. Share medication information with your clinician so the result can be interpreted correctly.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy