Albumin — Normal Range & Interpretation

Clinical Context

Albumin is the primary protein synthesized by the liver and makes up roughly 60% of total serum protein. It maintains plasma oncotic pressure, transports hormones, drugs, and fatty acids, and serves as a marker of hepatic synthetic function and nutritional status. Because albumin has a half-life of about 20 days, levels reflect chronic rather than acute changes.

Hypoalbuminemia points to decreased production in cirrhosis and advanced liver disease, increased loss through nephrotic syndrome or protein-losing enteropathy, and inadequate intake in protein-calorie malnutrition. Chronic inflammation, burns, and heart failure also drive albumin down. Hyperalbuminemia is uncommon and almost always reflects dehydration or hemoconcentration rather than a primary disease process. Low albumin alters the free fraction of highly protein-bound drugs such as phenytoin and warfarin and falsely lowers measured total calcium, requiring correction.

Board-style questions on albumin pair it with the hepatic panel and nutritional assessment. Expect questions linking low albumin to cirrhosis, nephrotic syndrome, and kwashiorkor-type malnutrition, and questions asking you to correct serum calcium when albumin is low. Candidates should recognize that albumin reflects chronic status, while prealbumin tracks acute nutritional changes, and that edema and ascites develop once albumin drops below approximately 2.5 g/dL.

Related Labs

• AST (SGOT) — U/L
• ALT (SGPT) — U/L
• ALP — U/L
• Total Bilirubin — mg/dL
• Direct Bilirubin — mg/dL

Sources

• MedlinePlus
• ARUP Consult