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Cotinine (Serum or Plasma, 24-Hour Urine)

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

This test measures cotinine, a metabolite of nicotine found in your blood or urine. It helps assess exposure to tobacco smoke or nicotine use over time.

Quick summary

["Cotinine helps track nicotine exposure, useful for monitoring smoking cessation efforts or environmental tobacco exposure."]

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

Key facts at a glance

LOINC
40418-6
Short code
Cotinine Mec Ql
Synonyms
Cotinine Mec Ql
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may order cotinine testing to evaluate whether you’ve been exposed to nicotine, especially if you’re trying to quit smoking or live with someone who smokes. It can also help detect secondhand smoke exposure in children or nonsmokers.

How Is the Test Performed?

For serum/plasma testing, a blood sample is drawn from a vein in your arm. For 24-hour urine testing, you’ll collect all urine over a full day in a special container. The sample is then sent to a lab for analysis.

What Do Results Mean?

Higher levels of cotinine suggest recent or ongoing nicotine exposure. Very low levels may indicate no exposure, while intermediate levels could reflect past exposure or inconsistent use. Results are not used to diagnose smoking status alone but are often part of a broader assessment.

What Are the Limitations?

Cotinine levels can vary based on diet, metabolism, and time since last exposure. False positives may occur with certain medications or environmental factors, so results should be interpreted by a healthcare provider.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Cotinine

Frequently asked questions

How long does it take to get results from this test?
Results are typically available within 1 to 3 business days, depending on your lab’s processing time. For urgent cases, some labs may provide preliminary results sooner, but final reports may take longer.
Can I influence my cotinine levels before the test?
Yes, avoid smoking, vaping, or chewing tobacco for at least 24 hours before testing if using a urine sample. For blood tests, nicotine exposure doesn’t typically affect results immediately, but consistency in your routine is key for accurate interpretation.
Is this test covered by insurance?
Coverage depends on your insurance plan and the reason for testing. If ordered by a healthcare provider for smoking cessation support or environmental exposure assessment, check with your insurer or provider for specifics. Some plans may require prior authorization.
  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