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Alpha-2-Antiplasmin

Published: July 27, 2026Updated: August 25, 2026

Alpha-2-antiplasmin is a protein that inhibits the enzyme plasmin, which is responsible for breaking down blood clots. This biomarker measures the functional activity of alpha-2-antiplasmin in the blood.

Quick summary

Alpha-2-antiplasmin measures the body's ability to inhibit clot breakdown.

Medically reviewed by WellAlly Editorial TeamLast reviewed August 25, 2026Editorial policy

Key facts at a glance

Units
%
Clinical utility
diagnostic
Result kind
quantitative
FDA-cleared
Roche Alpha-2-Antiplasmin, Stago Alpha-2-Antiplasmin
interpretation: {"text":"May indicate a deficiency in alpha-2-antiplasmin, leading to bleeding disorders.","label":"Low levels"}; {"text":"May suggest a thrombotic tendency or an acute phase response.","label":"High levels"}

Alpha-2-antiplasmin (A2AP) is a serine protease inhibitor that plays a crucial role in the regulation of fibrinolysis, the process that dissolves blood clots. By inhibiting plasmin, A2AP prevents the premature breakdown of clots, ensuring proper hemostasis.

The normal reference range for alpha-2-antiplasmin is 80–120%. Levels below this range may indicate a deficiency in the protein, which can lead to excessive bleeding due to uncontrolled fibrinolysis. Conversely, elevated levels may suggest a thrombotic tendency or acute phase response.

Measuring alpha-2-antiplasmin levels is essential in diagnosing conditions such as congenital A2AP deficiency, which is a rare bleeding disorder. It is also useful in assessing the risk of thrombosis and in monitoring patients with disseminated intravascular coagulation (DIC).

Frequently asked questions

What is the normal range for alpha-2-antiplasmin?
The normal reference range for alpha-2-antiplasmin is 80–120%.
What does a low alpha-2-antiplasmin level indicate?
A low level may indicate a deficiency in the protein, leading to excessive bleeding due to uncontrolled fibrinolysis.
  1. 1
    Alpha-2-Antiplasmin: A ReviewSource
  2. 2
    Role of Alpha-2-Antiplasmin in HemostasisSource

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 25, 2026. · Read our editorial policy