Skip to content

Antibody to *Giardia lamblia* (IgG) – Serum

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

This test checks for antibodies to the parasite *Giardia lamblia*, which can cause intestinal infections. It helps determine if you’ve been exposed to the parasite in the past.

Quick summary

["This test helps diagnose past exposure to *Giardia*, a common intestinal parasite."]

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

Key facts at a glance

LOINC
22306-5
Short code
G lamblia IgG Titr Ser
Synonyms
G lamblia IgG Titr Ser
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
8
Ref high
61
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82977
SNOMED
3110003
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 This Test Measures

The test detects IgG antibodies produced by your immune system in response to *Giardia lamblia* infection. These antibodies indicate past exposure, even if symptoms have resolved. The presence of antibodies suggests the body has encountered the parasite, but they do not confirm an active infection at the time of testing.

How the Test Works

A small blood sample is drawn from your arm. The serum portion is tested using an immunoassay method to identify IgG antibodies against *Giardia lamblia*. This helps differentiate between past infection and current illness.

Why It’s Done

Your healthcare provider may order this test if you’ve had symptoms like stomach pain, diarrhea, bloating, or nausea, especially after traveling to areas with known *Giardia* outbreaks. It’s also used in screening for travelers or individuals in settings with high exposure risk.

What to Expect

You’ll have a quick, painless blood draw. Results are typically ready within a few days. If positive, further testing (like stool samples) may be needed to confirm an active infection.

Reference range

Adult males: 8-61 U/L; Adult females: 5-36 U/LN/A

Specimen: serum

No special preparation required. Avoid fatty meals before the test if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

IgG Anti-Giardia Antibody

Frequently asked questions

What does a positive result mean?
A positive result means your body has likely been exposed to *Giardia lamblia* in the past, but it does not confirm an active infection. If symptoms persist, additional testing (such as stool exams) may be needed to check for ongoing infection.
What does a negative result mean?
A negative result suggests you either have never been exposed to *Giardia* or your immune system cleared the infection. However, symptoms could still occur if reinfection happens later.
How long do IgG antibodies last?
IgG antibodies can remain in your system for months to years after infection, sometimes for years. This is why the test is useful for detecting past exposure rather than active infection.
  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