Prolastin is a medication used in the treatment of Alpha-1 Antitrypsin Deficiency (AAT deficiency), a genetic condition that can lead to lung and liver disease. It is a purified form of human alpha-1 antitrypsin protein, which helps protect the lungs from damage caused by enzymes released during inflammation. By replenishing the deficient protein, Prolastin can help improve lung function and reduce the risk of further complications associated with AAT deficiency. The medication is typically administered via intravenous infusion.