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Explainer: What Is Plasma?

Protein-rich blood component helps keep us healthy and can be donated to create medicines for others.

A plasma donor looks at her phone while donating at a CSL Plasma center.

A Life-Giving Liquid

Did you know that the blood flowing through your body is mostly made up of plasma? While we’re all familiar with the critical importance of blood, many aren’t aware of the crucial role plasma plays in keeping us healthy.

Essentially, plasma is the straw-colored liquid portion of blood that is left over after red and white blood cells and platelets are removed. It’s made up of about 90 percent water, but plasma also contains salts, enzymes, antibodies and other proteins. These substances are important to helping the body fight off infections and play other important roles, such as clotting blood.

Plasma’s Importance in Medicine

Some people are born without one or more of the proteins that are typically found in plasma. Those people can benefit from medicines that are created from plasma from healthy donors.

To make those medicines, plasma is either drawn from donors through a process called plasmapheresis or separated out of a donation of whole blood. It then goes through a manufacturing process called fractionation, which allows individual proteins to be extracted and included in new medicines. Patients who are missing certain proteins receive these medicines, which replace the missing protein and enable their bodies to function more typically.

Conditions That Are Helped Through Plasma

People living with many different conditions can benefit from plasma-derived medicines and many depend on the therapies for their health.

Some examples include:

Hemophilia A

Hemophilia B

Von Willebrand disease

Primary immunodeficiency conditions

Alpha 1 Antitrypsin Deficiency

Hereditary Angioedema

How You Can Help

If you’re interested in learning more about plasma’s critical role in public health or would like information on how to donate, please visit