Donated plasma is used to create life-saving therapies for people with bleeding disorders, immune deficiencies, severe burns, and a range of other conditions. It’s one of the few biological materials that can’t be synthetically manufactured at scale, which is why donation centers are always in need of supply. The proteins inside plasma, once separated and purified, become the active ingredients in dozens of medical products used in hospitals and homes every day.
How Plasma Becomes Medicine
After collection, plasma goes through an industrial separation process called fractionation. The technique was originally developed at Harvard using ethanol precipitation, and a refined version of that same basic method remains the global industry standard today. Fractionation breaks plasma down into its individual protein components, primarily immunoglobulins (antibodies), albumin, and clotting factors. Each of these proteins is then purified further, tested for viruses, and packaged into specific medical products.
Chromatography and other purification techniques have expanded the number of usable proteins that can be harvested from a single plasma donation. A single batch of donated plasma may yield multiple therapies for completely different conditions, which is part of why the process is so efficient and so dependent on a steady supply of donors.
Treating Immune System Disorders
The single largest use of donated plasma is the production of immunoglobulin therapies, often called IVIG when given intravenously. These are concentrated antibodies pooled from thousands of donors, and they serve as a replacement immune system for people whose bodies can’t produce enough antibodies on their own. People with primary immunodeficiency diseases rely on regular immunoglobulin infusions, sometimes weekly or monthly for their entire lives, to fight off infections that a healthy immune system would handle automatically.
Immunoglobulin therapies also work as powerful immune modulators in conditions where the body’s defenses turn against itself. Approved uses include chronic inflammatory demyelinating polyneuropathy (a condition where the immune system attacks nerve coverings), immune thrombocytopenic purpura (where the body destroys its own platelets), and Kawasaki disease in children, which causes dangerous blood vessel inflammation. In Kawasaki disease specifically, the immunoglobulins work by binding to activated immune proteins and preventing them from forming complexes that damage tissue.
Clinical evidence also supports the use of these therapies in myasthenia gravis, a condition that causes severe muscle weakness, and in certain types of motor neuropathy where immune attacks on nerves disrupt movement. The antibodies in the infusion essentially neutralize the body’s own misdirected antibodies, a process that works because donated plasma from thousands of people contains a broad enough range of antibodies to counteract the harmful ones.
Clotting Factors for Bleeding Disorders
People with hemophilia A and hemophilia B are missing specific proteins their blood needs to clot. Without treatment, even minor injuries can cause prolonged or dangerous bleeding, and spontaneous bleeding into joints and muscles is common. Plasma-derived clotting factor concentrates replace what’s missing. Donated plasma is collected from many individuals, processed to isolate the clotting proteins, freeze-dried for stability, and treated to kill any potential viruses before reaching patients.
Hemophilia A patients need factor VIII, while hemophilia B patients need factor IX. Both are available as plasma-derived concentrates. Recombinant (lab-made) versions also exist, but plasma-derived products remain an important part of the treatment landscape, particularly for patients who develop inhibitors, which are antibodies that block the effectiveness of standard clotting factor therapy. Research from the FDA has shown that certain plasma-derived factor VIII formulations may actually be more effective at overcoming these inhibitors by triggering immune cells to eliminate the antibody-producing cells responsible.
Albumin for Burns, Trauma, and Shock
Albumin is the most abundant protein in plasma, making up more than 75% of its ability to hold fluid inside blood vessels. When someone suffers severe burns, their plasma protein levels drop sharply. Starting around 8 to 12 hours after a burn injury, the loss of these proteins allows fluid to leak out of blood vessels and into surrounding tissue, causing massive swelling. That swelling reduces oxygen delivery to tissues and increases pressure, compounding the injury.
Albumin infusions help restore the balance. Because albumin pulls fluid back into the bloodstream through osmotic pressure, it can maintain blood volume more effectively than saline or other non-protein fluids, reducing the total amount of fluid a burn patient needs. This matters because aggressive fluid therapy, while necessary, can worsen tissue swelling in both burned and unburned areas. Albumin is also used during major surgeries and in patients experiencing shock from blood loss, where maintaining adequate blood volume is critical to keeping organs functioning.
Fresh Frozen Plasma in Surgery
Fresh frozen plasma, or FFP, contains a full range of clotting factors and is used during major surgeries when patients develop bleeding that their own clotting system can’t control. Liver transplant surgery has traditionally required large volumes of FFP because patients with end-stage liver disease often have severely impaired clotting ability. The liver produces most of the body’s clotting factors, so when it fails, those proteins become dangerously low.
Correcting this during surgery requires substantial quantities of plasma, and medical teams must balance the benefit against risks. Transfusing FFP when there’s no active bleeding or confirmed clotting problem can actually cause complications, including blood clots. Current surgical practice is moving toward more targeted approaches, using specific clotting factor concentrates or fibrinogen as first-line treatments to reduce the overall need for FFP while still controlling bleeding effectively.
Protecting Newborns From Rh Disease
One of the most elegant uses of donated plasma is in preventing Rh incompatibility between mothers and their babies. When a mother has Rh-negative blood and her baby has Rh-positive blood (inherited from the father), the mother’s immune system can develop antibodies that attack the baby’s red blood cells. This can cause severe anemia, brain damage, or death in the newborn.
A product called RhoGAM, made from the plasma of donors with specific Rh antibodies, prevents this entirely. Rh-negative mothers receive an injection during the second trimester and again within days after delivery if the baby is Rh-positive. The injections stop the mother’s immune system from ever developing the dangerous antibodies in the first place. Women with Rh-negative blood also need injections after a miscarriage, abortion, amniocentesis, or any abdominal injury during pregnancy.
Treating a Genetic Lung Condition
Alpha-1 antitrypsin deficiency is a genetic condition where the body doesn’t produce enough of a protective protein that shields the lungs from damage. Without it, an enzyme normally used to fight infections slowly destroys lung tissue, leading to emphysema that can appear decades earlier than typical smoking-related lung disease.
The treatment is called augmentation therapy: purified alpha-1 antitrypsin protein, extracted from pooled donor plasma, is infused intravenously once a week. Clinical trials have shown this slows the progression of emphysema as measured by CT scans, with treated patients losing lung density at a lower rate than those receiving placebo. One large observational study found that augmentation therapy improved survival in patients with significant airflow obstruction. The therapy is recommended for patients whose lung function has declined to between 30% and 65% of predicted capacity, and also for those below 30%.
Why Demand Remains High
Many of these conditions require ongoing, sometimes lifelong treatment. A person with a primary immunodeficiency may need immunoglobulin infusions every few weeks for decades. Someone with hemophilia may infuse clotting factors multiple times per week. Alpha-1 patients receive weekly infusions indefinitely. Each of these treatments starts with donated plasma, and because the proteins must come from human donors, no factory or lab can replace the supply chain. The United States provides a significant portion of the world’s plasma supply, with collection centers processing millions of donations annually to meet global demand for these therapies.