Antithrombin (AT) Activity Blood Test

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Feature	Labcorp	Quest Diagnostics
Price	$48.99	$19.99
Results in	~3 business days	~5 business days
Sample type	Blood Plasma	Blood Plasma
Require fasting	No	No

About the test

This test evaluates the activity of antithrombin in the blood. It is used to help diagnose antithrombin deficiencies and to monitor the effectiveness of anticoagulant therapy in patients with clotting disorders.

Included biomarkers & Reference ranges

Biomarker	Reference range
Antithrombin III Activity Measures the activity of a protein that naturally helps prevent excessive blood clotting. Low levels are linked to an increased risk of blood clots.	—

Reference ranges vary by lab, age, and sex (M/F). Your report shows your exact range. Click any biomarker to see its optimal range and what your results mean.

Preparation

If you are taking unfractionated heparin or direct Xa inhibitor anticoagulant therapy, please consult your healthcare provider before collecting your sample.

Quest Diagnostics lists no special preparation for this test.

How it works

1. Order online No referral or insurance
2. Get a requisition By email in 24–72 hours
3. Visit a draw center Bring a matching photo ID
4. Get results Securely by email

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Consultations

Not sure how to read your results? We can help.

Schedule a consultation with a Hormunity specialist. We’ll walk through every marker, interpret what it means for you, and map out the next steps for your care.

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