On-the-spot blood liver panel: AST, ALT, albumin.

Why does liver panel testing matter in pharmacy?

Liver disease is frequently asymptomatic in its early stages. Many individuals with elevated liver enzymes or reduced albumin levels have no noticeable symptoms, making incidental detection at accessible points-of-care clinically relevant.

Why pharmacies should offer liver panel testing:

• Identify customers with early or undiagnosed liver dysfunction, including those with known metabolic risk factors.
• Monitor customers on medications with known or potential hepatic effects with a convenient on-site check.
• Provide a rapid hepatic screening option as part of a broader health check, for example, alongside cardiometabolic markers.
• Support timely referral to clinical care when results indicate abnormal liver function.

What does each marker in a liver panel mean? 

Alanine aminotransferase (ALT) 

ALT is an enzyme found in high concentrations in the liver. Its main role is metabolic: it helps the body convert amino acids into energy. Under healthy conditions, only small ALT amounts circulate in the blood. When liver cells are damaged or stressed, ALT leaks out into the bloodstream.

Because ALT is found predominantly in the liver, with significantly lower concentrations in other tissues, it is considered more liver-specific than AST (see below). A raised ALT is one of the most sensitive early indicators of hepatocellular injury. The degree of elevation provides important clinical context: mildly elevated values may reflect fatty liver disease or a medication effect, while markedly elevated values tend to point toward more acute or severe liver conditions.

The half-life of ALT is approximately 47 hours, meaning levels fall relatively quickly once the underlying injury resolves. ALT values are normally higher in males than in females, and they also correlate with body weight, individuals with a higher BMI tend to have a higher normal ALT range.

Aspartate aminotransferase (AST)

AST participates in the same amino acid metabolism pathways as ALT, and like ALT, it is released into the bloodstream when liver cells are damaged. However, AST is present as two distinct forms (a cytosolic and a mitochondrial isoenzyme) and, unlike ALT, it is found in significant amounts in many tissues beyond the liver, including cardiac and skeletal muscle, kidneys, the brain, and red blood cells. This makes AST less liver-specific than ALT: an elevated AST is not automatically a sign of liver disease, and non-hepatic causes such as muscle injury, high-intensity exercise, or hemolysis should be considered, particularly when ALT is normal.

This is why measuring AST alongside ALT is more informative than either marker alone. The two tests together give a fuller picture of what's happening in the liver and help guide the next steps.

Like ALT, AST values are normally higher in males than in females.

Albumin

Albumin is the most abundant protein in blood plasma, and the liver is its primary site of production. It performs several essential functions: maintaining oncotic pressure (which keeps fluid within blood vessels), transporting hormones, vitamins, fatty acids, and enzymes throughout the body, and contributing to pH buffering.

Because albumin reflects the synthetic capacity of the liver over time (its half-life is approximately 21 days) it is a useful marker of chronic or sustained liver dysfunction rather than acute injury. Low albumin is seen in chronic liver disease and cirrhosis, and also in prolonged malnutrition, systemic inflammation, and conditions involving protein loss such as nephrotic syndrome. These non-hepatic causes mean albumin should always be interpreted in clinical context alongside the aminotransferases and other findings.

Unlike ALT and AST, which rise when liver cells are damaged, albumin falls when the liver can no longer produce adequate amounts. This is why albumin is a complementary marker that captures a different axis of hepatic health.

How is the liver panel measured?

• Sample: Small capillary whole blood sample (fingerprick)

• Markers measured: ALT, AST, albumin

• Units: ALT and AST in U/L; albumin in g/L

• Result time: Minutes

Interpretation: Liver panel results are most informative when all three markers are considered together rather than in isolation. Always follow the instructions for use (IFU) provided with your testing device and kit to ensure accurate results in your point-of-care setting. Results should be interpreted using local reference ranges and in the personal context of each individual customer.

Liver panel testing with Igloo Reader Pro

The liver panel can be measured from a small capillary whole blood sample using Igloo Reader Pro within pharmacies or other point-of-care settings. All three markers are analyzed from a single sample, with results available within minutes, with no laboratory processing required.

Benefits of liver panel testing with Igloo Reader Pro in pharmacies:

• Deliver fast, quantitative results across three hepatic markers at the point-of-care.
• Screen for liver dysfunction in customers with metabolic risk factors in a single, brief appointment.
• Monitor customers on potentially hepatotoxic medications without requiring a laboratory referral.
• Expand preventive health service offerings and support timely clinical follow-up.

Best practices for liver panel testing

• Fasting: ALT, AST, and albumin are not significantly affected by recent food intake. Fasting is not required, but standardizing conditions for repeat testing improves comparability over time.

• Medications and supplements: Liver enzyme levels can be affected by a range of medications, including certain antibiotics, azole antifungals, anticonvulsants, and herbal or dietary supplements. Always note a customer's medication and supplement history when interpreting results.

• Alcohol: Recent alcohol consumption can transiently elevate ALT and AST. Customers should ideally avoid alcohol before testing for a representative result.

• Exercise: Intensive physical activity can elevate AST, and to a lesser extent ALT, due to muscle turnover. Note recent activity levels when interpreting results.

• Repeat testing: A single liver panel result is informative, but trends over time are more clinically meaningful. Customers with borderline values benefit from follow-up monitoring.

Learn more about the liver panel >

Why should pharmacies offer liver panel testing?

Liver disease is one of the most underdiagnosed conditions in adults, yet the markers that signal it are simple, fast, and measurable at the point-of-care setting. For pharmacies, that is a significant opportunity.

Many adults with metabolic risk factors such as obesity, type 2 diabetes, or metabolic syndrome have never had their liver enzymes checked despite being at elevated risk. Customers on long-term medications with known hepatic effects benefit from periodic monitoring as part of a routine medication review. And because liver dysfunction frequently co-occurs with cardiovascular and metabolic conditions, adding a liver panel alongside a lipid panel or HbA1c creates a more complete preventive health picture in a single appointment, without additional complexity for the customer or the pharmacy team.

Literature

• Shang Hong, Wang Yusan, Shen Ziyu et al. National Clinical Laboratory Procedures [M]. 4th edition. Beijing: People's Medical Publishing House, 2014: 279–283. (Cited in the Instructions for Use (IFU) of the Konsung DiaCard-6 test card (P/N: 128010203, Rev. 1.1, February 2024))
• WS/T404.1-2012. Reference intervals for common clinical biochemical tests - Part 1: Serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyltransferase. WS/T404.1-2012. Reference intervals for common clinical biochemistry tests - Part 2: Serum total protein and albumin. (Cited in the Instructions for Use (IFU) of the Konsung DiaCard-6 test card (P/N: 128010203, Rev. 1.1, February 2024))
• Lala V, Zubair M, Minter DA. Liver Function Tests. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2023.
• Vroon DH, Israili Z. Aminotransferases. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd ed. Boston: Butterworths; 1990. Chapter 99.
• National Library of Medicine, MedlinePlus. AST Test.
• National Library of Medicine, MedlinePlus. ALT Blood Test.
• National Library of Medicine, MedlinePlus. Albumin Blood Test.
  Kwo PY, Cohen SM, Lim JK. ACG Clinical Guideline: Evaluation of Abnormal Liver Chemistries. Am J Gastroenterol. 2017;112(1):18–35. doi: 10.1038/ajg.2016.517
• Mayo Clinic. Liver function tests.
  Chalasani N et al. Features and Outcomes of 899 Patients With Drug-Induced Liver Injury: The DILIN Prospective Study. Gastroenterology. 2015;148(7):1340–1352.
• NIH LiverTox: Clinical and Research Information on Drug-Induced Liver Injury.

Disclaimer

This information is educational and does not qualify for a medical advice. Always use local reference ranges and consult a healthcare professional for diagnosis and treatment.