Skip to content

Alpha-1 Antitrypsin (A1AT) Serum Concentration

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

This test measures the level of Alpha-1 Antitrypsin, a protein produced by the liver that helps protect the lungs from damage caused by enzymes released during inflammation.

Quick summary

["A1AT helps prevent lung disease and supports immune function; low levels may indicate genetic risk or liver disease."]

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

Key facts at a glance

LOINC
77459-6
Short code
Deprecated Hind+Mid ft XR 1V
Synonyms
Deprecated Hind+Mid ft XR 1V
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
xr
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 Is Done

Your doctor may order an Alpha-1 Antitrypsin test if you have symptoms of lung disease (such as chronic cough, shortness of breath) or if you have a family history of Alpha-1 Antitrypsin deficiency. It may also be used to monitor liver health or assess risk for conditions like emphysema or cirrhosis.

What to Expect Before the Test

No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw blood, which usually causes only minor discomfort. If you’re on blood thinners, let your doctor know before the test.

What the Results Mean

Results are compared to a standard range for healthy adults. Very low levels may suggest a genetic disorder (Alpha-1 Antitrypsin deficiency), liver disease, or other conditions. High levels may be normal or linked to certain medications or liver issues.

Possible Risks and Side Effects

The most common side effect is a slight bruise or mild pain at the injection site. Rarely, there may be a reaction to the needle or blood drawing. If you experience dizziness, fainting, or excessive bleeding, inform your healthcare provider immediately.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

A1AT

Frequently asked questions

What causes Alpha-1 Antitrypsin deficiency?
Alpha-1 Antitrypsin deficiency is usually genetic, passed down through families. It occurs when a mutation in the gene causes the liver to produce an abnormal form of the protein, which then accumulates and damages organs, particularly the lungs and liver.
Can lifestyle changes help if I have low A1AT levels?
While lifestyle changes alone won’t reverse genetic deficiency, they may help manage symptoms. Quitting smoking, avoiding secondhand smoke, and maintaining a healthy weight can reduce lung disease risk. If liver involvement is suspected, follow your doctor’s advice for diet, exercise, and monitoring.
How often should I get this test?
If you have a confirmed diagnosis of Alpha-1 Antitrypsin deficiency, your doctor may recommend regular testing (every 1–3 years) to monitor lung or liver function. If you’re asymptomatic but have a family history, your doctor may check levels less frequently or only during specific health evaluations.
  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