Antibody to Advil (Naproxen) in Serum
This test measures antibodies your body produces in response to the medication naproxen (commonly sold as Advil or Aleve). It helps assess whether you have developed an immune reaction to this medication.
["This test helps identify potential allergic or immune responses to naproxen."]
Key facts at a glance
- LOINC
- 31282-7
- Short code
- CAV1AB
- Synonyms
- CAdV1 Ab Ser Ql
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top vacutainer tube without anticoagulant
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Serum neutralization test (SNT), Enzyme-linked immunosorbent assay (ELISA), or Virus neutralization test (VNT)
- CPT
- 86657
- SNOMED
- 385521001
- Specimen volume
- 1-2 mL of serum (minimum 0.5 mL)
- Stability
- Serum is stable for 7 days at 2-8°C. For extended storage, freeze at -20°C or below for up to 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 24–120 hours
- Order
- routine
Why Might This Test Be Ordered?
Your healthcare provider may recommend this test if you’ve experienced unusual symptoms—such as rash, itching, swelling, or difficulty breathing—while taking naproxen. It can also be used to monitor rare cases of severe allergic reactions (e.g., anaphylaxis) or to check for immune-related side effects.
What Does a Positive Result Mean?
A positive result suggests your body has detected naproxen as a foreign substance, triggering an immune response. This doesn’t always mean you’re allergic, but it indicates your immune system is reacting to the medication. Further evaluation by your doctor may be needed to determine next steps.
How Is This Test Performed?
A blood sample is taken from a vein in your arm. The serum (liquid part of blood) is then tested for naproxen-specific antibodies using an immunoassay method, which detects the presence of these antibodies in your blood.
What Are Common Symptoms to Watch For?
If you experience symptoms like hives, swelling in your face or throat, wheezing, chest tightness, or severe stomach pain shortly after taking naproxen, seek medical attention immediately. These could signal an allergic reaction.
Reference range
Negative: No detectable antibodies detected. Positive: Antibodies detected, indicating prior exposure or vaccination. Titer results reported as reciprocal of highest dilution showing positive reactivity.N/A
No special patient preparation required. Fasting is not necessary. Inform the veterinarian of any recent vaccinations, as vaccination with modified live CAV-1 or combined vaccines (e.g., DHPP) may produce detectable antibody titers.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is primarily used to investigate suspected allergic reactions to naproxen. While antibodies indicate an immune response, they don’t always predict whether you’ll have symptoms. Your doctor may correlate results with your symptoms and medical history to guide further testing or adjustments to your medication.
Short name
Naproxen Antibody (Serum)
Frequently asked questions
What does a positive antibody test mean for my health?
Can I still take naproxen if my antibody test is positive?
How soon after taking naproxen can I get this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 15, 2026. · Read our editorial policy