Human Albumin

Human albumin is a purified plasma-derived protein preparation containing predominantly albumin, the major protein naturally present in human blood plasma. It belongs to the class of plasma-derived colloid solutions and is administered by intravenous infusion. Albumin contributes substantially to plasma oncotic pressure, helping retain fluid within the circulation, and also binds and transports various endogenous and exogenous substances. When administered clinically, albumin can expand or maintain intravascular volume and can help restore circulating volume when significant fluid shifts or losses have occurred. Different formulations are available, commonly as approximately 5% solutions for volume replacement and more concentrated solutions such as 20% or 25% for selected indications where oncotic effects are required. Human albumin is clinically important in situations such as documented hypovolemia, selected cases of hypoalbuminemia, and prevention of circulatory volume depletion following large-volume paracentesis for cirrhotic ascites. Depending on the product and jurisdiction, additional indications may include ovarian hyperstimulation syndrome, certain renal conditions, acute respiratory distress syndrome, or neonatal hyperbilirubinemia. Treatment should be based on the patient's clinical volume status and the specific approved product indication rather than albumin concentration alone.

Human albumin has been used clinically for decades as a plasma-derived colloid for volume restoration and maintenance. Modern preparations are manufactured from screened human plasma using purification and validated manufacturing processes designed to reduce the risk of transmission of infectious agents. The European Medicines Agency developed a harmonised core Summary of Product Characteristics for human albumin solution, with Revision 3 receiving a legal effective date of 1 February 2019. In the United States, the FDA has approved albumin human products for restoration and maintenance of circulating blood volume where volume deficiency has been demonstrated and use of a colloid is appropriate; individual formulations have different approval histories and indications. Current U.S. labeling for certain albumin human 5% and 25% products lists an initial approval year of 2006. Clinical evidence and regulatory assessments have supported its use in volume deficiency and selected specialized clinical settings, although indications differ between formulations and jurisdictions.

Human albumin is used primarily for restoration or maintenance of circulating blood volume when volume deficiency has been demonstrated and a colloid is clinically appropriate. Depending on the concentration and specific product, approved indications may include hypovolemia, selected cases of hypoalbuminemia, and prevention of circulatory volume depletion following paracentesis for cirrhotic ascites. Some concentrated albumin products also carry indications for ovarian hyperstimulation syndrome, acute nephrosis, adult respiratory distress syndrome, and hemolytic disease of the newborn. Albumin may be used alone for volume replacement or alongside other treatments, such as diuretics in selected patients with acute nephrosis. In cirrhosis, albumin may be administered after large-volume paracentesis to reduce the risk of circulatory dysfunction. It is not appropriate to use albumin simply to correct a low laboratory albumin value without considering the underlying clinical condition and volume status. Approved uses vary by formulation, concentration, and regulatory jurisdiction.

Human albumin is administered by intravenous infusion, with the concentration, dose and infusion rate adjusted according to the patient's clinical condition, body size, severity of illness, ongoing fluid or protein losses and hemodynamic response. For commonly labeled U.S. products, dosing may include an adult initial dose of 25 g for hypovolemia and 50–75 g for hypoalbuminemia, while prevention of circulatory volume depletion after paracentesis is commonly dosed at 8 g for each 1,000 mL of ascitic fluid removed. Some 20% or 25% formulations have additional indication-specific regimens, including repeated dosing for ovarian hyperstimulation syndrome or short courses for selected acute nephrosis. The total daily dose should generally not exceed 2 g/kg according to applicable U.S. product labeling. Treatment duration is indication-specific and should be guided by hemodynamic status, fluid balance and clinical response rather than serum albumin concentration alone.

Common adverse effects of human albumin are generally related to infusion or changes in intravascular volume and may include flushing, chills, fever, nausea, headache, changes in blood pressure, injection or infusion-site discomfort, and mild hypersensitivity reactions. Concentrated albumin can produce fluid shifts that may cause discomfort or symptoms associated with changes in circulating volume. Most reactions are manageable when the infusion rate and dose are adjusted appropriately. The frequency and nature of adverse effects can vary between products, concentrations and individual patients.

Important risks include severe hypersensitivity or anaphylactic reactions, hypervolemia, pulmonary edema, cardiovascular overload, electrolyte disturbances and hypotension or other hemodynamic changes. Excessive or excessively rapid administration can increase intravascular volume and may be particularly hazardous in patients with cardiac failure, pulmonary edema, severe anemia with normal or increased intravascular volume, or other conditions where volume expansion presents a risk. Concentrated albumin should be administered with appropriate attention to hydration and fluid balance. Electrolytes, hematocrit, coagulation status and hemodynamic parameters may require monitoring according to the clinical situation. Albumin preparations are derived from human plasma; although manufacturing controls substantially reduce infectious risk, transmission of infectious agents cannot be regarded as impossible. Severe hypersensitivity requires immediate interruption and appropriate emergency management.

Before treatment, clinicians should assess the patient's intravascular volume status, cardiac and renal function, fluid balance, hematocrit and relevant electrolyte values. Particular caution is required in patients at risk of hypervolemia or hemodilution and in those with cardiac failure or pulmonary edema. Concentrated albumin should be accompanied by appropriate assessment of hydration and circulatory status. Human albumin has no major classic metabolic drug interactions because it is a naturally occurring plasma protein rather than a conventionally metabolised small-molecule medicine. However, albumin can alter intravascular volume and may influence the distribution of certain protein-bound substances, so concomitant therapies should be considered in the overall clinical assessment. Albumin should not be diluted with sterile water for injection because this can cause hemolysis. Vaccine-specific interaction considerations are generally not a principal issue with albumin therapy.

Confirm the indication, albumin concentration and intended clinical objective before administration. Dose should be guided primarily by hemodynamic and fluid-status assessment rather than by an isolated serum albumin result. During infusion, monitor blood pressure, pulse, respiratory status, urine output and other relevant measures of circulatory response, particularly when concentrated albumin or large volumes are administered. Monitor electrolytes, hematocrit and coagulation parameters when clinically appropriate. For patients undergoing large-volume paracentesis, verify the volume of ascitic fluid removed and follow the applicable albumin replacement protocol. Pharmacists should verify concentration, storage requirements, product-specific indications and infusion instructions because albumin preparations are not necessarily interchangeable. Do not dilute albumin with sterile water for injection, and inspect the solution before administration according to the product instructions.