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Total IgG Antibody to Giardia Lamblia (Serum/Plasma)

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

This test measures antibodies in your blood that your immune system produces in response to Giardia lamblia, a parasite that can cause intestinal infections.

Quick summary

["Helps diagnose past or ongoing exposure to Giardia infection."]

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

Key facts at a glance

LOINC
35285-6
Short code
tTG IgA Ser Ql
Synonyms
tTG IgA Ser Ql
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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

What Does This Test Measure?

The test detects IgG antibodies, a type of immune protein your body makes when it encounters Giardia. These antibodies stay in your system for a longer period after infection, helping your immune system remember the parasite for future protection.

Why Might You Need This Test?

Your healthcare provider may order this test if you’ve had symptoms like stomach cramps, diarrhea, bloating, or nausea—especially if you’ve traveled to areas with known Giardia outbreaks or live in a setting where contamination is common (e.g., water sources). It can also be used to confirm a diagnosis if other tests are inconclusive.

How Is the Test Done?

A blood sample is taken from a vein in your arm. The sample is sent to a lab where it’s analyzed using an immunoassay method to identify the presence of Giardia-specific IgG antibodies.

What Are Possible Results?

A positive result indicates your immune system has likely encountered Giardia in the past, meaning you may have had an infection. A negative result suggests no detectable antibodies, which could mean you’ve never been exposed or the infection has cleared.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Giardia IgG Antibody

Frequently asked questions

How long do Giardia IgG antibodies stay in the blood?
Giardia IgG antibodies can remain detectable in the blood for months to years after infection, sometimes even years later. This is because the immune system retains these antibodies as a memory response, which helps protect against reinfection.
Can this test diagnose an active Giardia infection?
No, this test alone cannot diagnose an active Giardia infection. It only shows past exposure. For active infection, your doctor may recommend additional tests, such as stool samples for parasite detection or other diagnostic tools.
What if my test result is positive but I don’t have symptoms?
A positive result doesn’t always mean you’re currently sick. It simply means your body has been exposed to Giardia at some point. If you’re concerned, discuss your symptoms and medical history with your healthcare provider to determine the next steps.
  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