What is an AST (Aspartate Transaminase) Blood Test?

The AST blood test, also known as SGOT (Serum Glutamic-Oxaloacetic Transaminase), measures the amount of the enzyme aspartate transaminase in your bloodstream. This enzyme helps convert amino acids into energy, a process essential to normal liver and muscle function.

Under normal circumstances, AST remains inside cells of the liver, heart, skeletal muscles, kidneys, and brain. However, when these cells are damaged or inflamed, AST leaks into the bloodstream, resulting in higher measurable levels.

At London Blood Tests, the AST test is often part of a liver function panel, but it can also be performed as an individual marker. It helps detect early liver inflammation, monitor ongoing liver conditions, or evaluate the effects of medications and alcohol on liver health.

Our laboratory uses advanced enzymatic spectrophotometry methods under UKAS accreditation, ensuring precise, clinically validated results. Following your test, you can book a GP consultation to discuss your results and receive professional recommendations on next steps or treatment.

Benefits of an AST (Aspartate Transaminase) Test

• Detects Early Liver Damage
  AST levels rise when liver cells are injured, making it an early marker for hepatitis, fatty liver disease, or medication-induced liver stress.

• Assesses Muscle and Heart Health
  Since AST is also present in muscle and heart tissue, the test can help identify muscle trauma, heart inflammation, or conditions like rhabdomyolysis.

• Monitors Chronic Liver Disease
  For individuals with ongoing liver conditions such as hepatitis B, hepatitis C, or non-alcoholic fatty liver disease (NAFLD), the AST test helps track disease progression or recovery.

• Evaluates Medication or Alcohol Effects
  Some medications and alcohol can elevate liver enzymes. Regular AST testing allows safe monitoring of potential liver side effects.

• Part of a Comprehensive Liver Function Panel
  When combined with other markers such as ALT, ALP, and bilirubin, AST provides a more complete view of liver function and metabolic health.

• Supports Preventive Health Checks
  AST testing can identify subtle liver changes before symptoms appear, enabling lifestyle changes or interventions that prevent long-term complications.

• Includes GP Consultation for Clinical Interpretation
  Your results are reviewed with a London Blood Tests GP, who can explain what they mean, identify causes, and guide you on treatment or follow-up investigations.

Why Do I Need an AST Blood Test?

An AST blood test is recommended for anyone with symptoms or risk factors related to liver, heart, or muscle function. It can help detect hidden damage early, even before physical symptoms become obvious.

You may need this test if you experience:

• Fatigue or weakness
• Yellowing of the skin or eyes (jaundice)
• Dark urine or pale stools
• Loss of appetite, nausea, or vomiting
• Swelling in the legs or abdomen
• Pain or discomfort in the upper right abdomen
• Muscle pain or stiffness after medication or injury

You may also require AST testing if:

• You consume alcohol regularly
• You’re taking medications known to affect the liver (e.g., statins, antibiotics, anti-seizure drugs)
• You have diabetes, obesity, or metabolic syndrome
• You’re undergoing treatment for liver disease or hepatitis

Early testing allows your GP to assess the extent of liver or muscle injury and determine whether lifestyle changes, medication adjustment, or further imaging is needed.

Step-by-Step: How the Test Works

In-Clinic Testing

1. Book Your Appointment
   Schedule your visit online at your nearest London Blood Tests clinic. Walk-ins are also available depending on capacity.
2. Pre-Test Discussion (Optional)
   If you have liver-related symptoms or medication concerns, you can consult our GP before testing to ensure the correct panel is selected.
3. Sample Collection
   A small blood sample is taken from a vein in your arm by a trained clinician. The procedure takes just a few minutes.
4. Laboratory Analysis
   Your sample is analysed in a UKAS-accredited lab using spectrophotometric enzymatic testing to measure AST activity in units per litre (U/L).
5. Quality Control & Verification
   All samples are reviewed and verified by biomedical scientists to ensure accuracy.
6. Results Delivery
   Your results are typically available within 1–2 business days, accessible securely online or via email.
7. GP Consultation & Medical Advice
   After receiving your results, you can book a GP consultation to discuss what your AST levels mean, possible causes of elevation, and any recommended follow-up tests (such as ALT, ALP, or ultrasound).

At-Home Blood Draw (UK-Wide Service)

1. Book Your Appointment
• Schedule your at-home or hotel phlebotomy visit online or by phone.
• Choose a date and time that suits your schedule, same-day or next-day appointments are often available in London and surrounding areas.
2. Professional Phlebotomist Visit
• A trained and certified phlebotomist arrives at your location equipped with sterile, single-use medical supplies.
• The service is discreet, convenient, and follows strict infection-control standards.
3. Sample Collection
• The phlebotomist draws a small venous blood sample (1–2 serum tubes) from your arm, the same as in-clinic.
• The process takes approximately 10 minutes and is comfortable, hygienic, and minimally invasive.
4. Sample Handling and Transport
• Your sample is labelled, sealed, and placed in a temperature-controlled biohazard container.
• It is then couriered directly to our UKAS-accredited laboratory the same day for analysis.
5. Laboratory Testing
• The lab performs the ELISA and immunofluorescence (IFA) assays to detect IgM and IgG antibodies for multiple arboviruses.
• All testing follows ISO 15189 quality standards to ensure precise results.
6. Results Delivery
• Results are typically available within 1-2 business days after lab receipt.
• You will be notified by email once your digital report is ready in your secure online account.
7. Optional GP Consultation
• If your test is positive or you have ongoing symptoms, you can book an optional GP consultation (via phone or video) for expert interpretation, travel advice, and next-step recommendations.

Your AST Blood Test Results – Explained

Your result is reported as units per litre (U/L), the amount of enzyme activity in your blood.

• Normal Range (Adults):
• Men: 10–40 U/L
• Women: 9–32 U/L
• Mildly Elevated AST (Up to 2× upper limit):
• May indicate minor liver irritation due to medications, alcohol, or physical exertion.
• Usually resolves once the underlying cause is managed.
• Moderately Elevated AST (2–5× upper limit):
• Could signal liver inflammation such as viral hepatitis, fatty liver disease, or alcohol-related liver injury.
• GP follow-up and additional liver markers (ALT, ALP, GGT, bilirubin) are usually advised.
• Severely Elevated AST (>5× upper limit):
• Suggests significant liver damage, acute hepatitis, or muscle injury.
• Immediate GP evaluation is recommended for diagnosis and treatment.
• Low AST Levels:
• Uncommon and usually not clinically significant, but may occasionally relate to vitamin B6 deficiency or muscle mass loss.

After reviewing your report, your London Blood Tests GP will help interpret whether changes are due to liver, heart, or muscle causes and guide appropriate management.