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Immunoassay for Immunoglobulin G (IgG) Subclass 1 (IgG1) in Serum

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

This test measures the level of a specific type of antibody (IgG1) in your blood, which is part of your immune system’s response to infections and diseases.

Quick summary

["IgG1 helps fight certain infections and plays a role in long-term immunity."]

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

Key facts at a glance

LOINC
96464-3
Short code
IP3R 1 IgG Ser Ql IF
Synonyms
IP3R 1 IgG Ser Ql IF
Category
coagulation
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
if
CPT
82784
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 This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms or conditions linked to abnormal IgG1 levels, such as autoimmune diseases, chronic infections, or immune system disorders. It may also be used to monitor treatment responses or diagnose specific immune-related conditions.

What to Expect Before the Test

No special preparation is needed. You may have blood drawn from a vein in your arm, similar to other blood tests. If you’re on blood thinners, let your provider know before the test.

What the Test Results Mean

Results are compared to a general reference range for IgG1 levels in healthy adults. Abnormal results may indicate immune system dysfunction, certain infections, or other health issues. Your provider will discuss these results with you.

Common Conditions Linked to IgG1 Levels

IgG1 levels can be relevant in diagnosing or monitoring conditions like chronic infections (e.g., HIV, hepatitis), autoimmune diseases (e.g., lupus, rheumatoid arthritis), or immune deficiencies. It may also help assess vaccine responses or immune-related cancers.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

IgG1 Subclass Test

Frequently asked questions

What questions might you have about this test?
Will fasting affect my IgG1 test? No, fasting is not required for this test, as it measures IgG1 levels in serum, which are not influenced by recent food intake.
How long will it take to get my results?
Results are typically available within 1 to 3 business days, depending on your lab’s processing time. Your healthcare provider will contact you once they are ready.
Can I have my IgG1 test repeated if my results are abnormal?
Yes, if your results are outside the expected range, your provider may recommend retesting or additional tests to better understand the cause. Follow-up may also include further evaluation by a specialist.
  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