Montelukast-Dependent Neutrophil IgG Antibody, Serum/Plasma — Qualitative
A specialized qualitative test for montelukast-dependent IgG that reacts with neutrophils, used when a drug-related immune blood-cell reaction is suspected.
["A positive result may support an immune-mediated blood-cell reaction to montelukast."]
Key facts at a glance
- LOINC
- 72988-9
- Short code
- Montelukast (neut) IgG SerPl Ql FC
- Synonyms
- Montelukast (neut) IgG SerPl Ql FC
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- flow-cytometry
- CPT
- 84484
- SNOMED
- 302774002
- 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
What is this test?
This blood test looks for IgG antibodies that react with neutrophils, a type of white blood cell, only when montelukast is present. It is not a routine medication-level test and is generally ordered only when a drug-related immune reaction is suspected.
Why might I need this test?
Your clinician may order it after investigating a low white-blood-cell count, a sudden reduction in neutrophils, or other signs of a possible adverse immune reaction to montelukast.
How is the test performed?
A serum or plasma sample is obtained from a blood draw. The laboratory tests whether the sample contains IgG that binds to neutrophils in the presence of montelukast and reports the result as positive, negative, or otherwise indeterminate.
How do I prepare for the test?
No special preparation is usually required. Tell the healthcare team which montelukast products you take, when you started them, and when symptoms began; do not stop prescribed medication without medical guidance.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result may indicate that montelukast is triggering an immune-mediated reaction involving neutrophils, which can contribute to a low neutrophil count. Results must be interpreted with your medication history, symptoms, blood counts, and other laboratory findings. A negative or indeterminate result does not completely exclude a drug-related reaction.
Short name
Montelukast-Dependent Neutrophil IgG
Frequently asked questions
Is this the same as a routine montelukast blood-level test?
What does a positive result mean?
Should I keep taking montelukast while waiting for results?
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 17, 2026. · Read our editorial policy