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Opioid Mass Concentration in Serum

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

This test measures the amount of opioids, such as fentanyl, morphine, or codeine, in your blood serum. Opioids are medications used for pain relief.

Quick summary

["Opioid levels help doctors assess drug exposure, monitor pain treatment, or detect potential misuse."]

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

Key facts at a glance

LOINC
65808-8
Short code
Nortapentadol Ur-mCnc
Synonyms
Nortapentadol Ur-mCnc
Category
chemistry
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

Why Is This Test Done?

Your healthcare provider may order this test if you’re on opioid pain medication, experiencing suspected opioid overdose, or if you’re being evaluated for substance use. It can also help track how your body processes opioids or check for drug interactions.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw blood. The process usually takes a few minutes, and you may feel a brief pinch. If you’re on blood thinners, let your provider know beforehand.

What Happens During the Test?

The blood sample is sent to a lab where it’s analyzed using a high-performance liquid chromatography (HPLC) method to detect and measure opioid compounds. Results are reported as mass concentration in the serum.

What Do the Results Mean?

Results provide a quantitative measure of opioid presence, helping healthcare providers determine drug levels, assess toxicity, or guide treatment adjustments. Interpretation depends on clinical context, such as your medical history or prescribed medications.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Opioid Levels Play a Critical Role in Pain Management and Safety

Short name

Opioid Level (Serum)

Frequently asked questions

How long does it take to get my test results?
Results are typically available within 1–3 business days, depending on lab processing times. Your provider will contact you once they’re ready.
Can I drink alcohol before this test?
No, avoid alcohol for 24 hours before testing, as it may interfere with opioid detection or affect blood chemistry.
Will this test show all opioids, or just the ones I’m prescribed?
This test detects a broad range of opioids, including prescription medications and illicit drugs, not just those prescribed to you.
  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