A high AST result can come from the liver, the heart or other muscles, so the next step is to read it beside ALT, gamma GT and creatine kinase. At Blood London the AST blood test costs £39.38 plus a £50 blood draw, the result is ready one day after the sample reaches the lab, and you walk in at 117a Harley Street or book online.
One point on cost before anything else: the liver function test (£72.50 plus the same £50 draw) already includes AST. Booking AST and the liver function test together means paying for AST twice, so choose one or the other. The full comparison is further down.
The clearest way to see what it shows is to follow three results and what a doctor would do with each. They are examples, not real patients.
Where AST comes from
When liver, muscle, heart or red blood cells are stressed, a little AST leaks into the blood, and the test measures how much. Your laboratory report prints its own range beside the number.
Three neighbours help to place it. ALT is found mostly in the liver, creatine kinase comes from muscle, and gamma GT is sensitive to alcohol and the bile ducts. Read together, they show where an AST rise began.
What happens to your sample at Blood London
A phlebotomist takes a venous sample from your arm at Suite E, 117a Harley Street. The sample reaches the lab the same day, and the AST result is ready one day after that. It is analysed at a UKAS-accredited London laboratory, and the report is sent directly to you.
Red blood cells hold AST too, so a sample in which they have broken open, called haemolysis, can show a falsely high result. It mostly comes from how the blood is drawn and handled. A careful venous draw by our phlebotomist and same-day delivery to the lab help, although no clinic can rule it out entirely. Tell the phlebotomist about alcohol in the last day or two and any hard exercise, because both can move these results.
What else can raise AST
- Alcohol, including a few heavier days of drinking.
- Fatty liver.
- Some prescribed and over-the-counter medicines.
- Muscle injury or very hard exercise.
- Viral hepatitis.
A raised result is a prompt for a conversation, and most causes can be looked into calmly. If a raised result comes with yellow skin or eyes, dark urine or feeling very unwell, get medical advice the same day.
Three results and the next step for each
Raised after a hard gym session
The first person did a heavy leg session the day before. AST is up, and creatine kinase would likely be up too. Worked muscle releases AST, and the rise can last several days, up to about a week. Very heavy training can lift ALT a little as well, so the pattern, with AST and creatine kinase rising more than ALT, tells a doctor more than ALT being exactly normal.
"With a raised AST on its own, I always ask about exercise first. A hard session at the gym can push it up for several days. Then I look at the ALT next to it."
Dr Mohammad Bakhtiar, Clinical Lead, GMC 4694470
A sensible next step is a repeat after about a week without heavy training. If you would like the muscle side checked straight away, add creatine kinase (£46.88) to the same draw. AST plus creatine kinase comes to £136.26 with the £50 draw.
Raised alongside ALT
The second person has AST and ALT both above range. With ALT moving too, the liver comes into focus. A doctor would ask about alcohol, regular medicines and recent illness, and would want the other liver markers before saying more. Many things can lift both enzymes, so the pattern is where the conversation starts.
The liver function test is the natural next step here, and the next section gives its price. This is also the point to book the £75 Blood London doctor review, so the pattern is explained to you in person.
Slightly raised on its own
The third person has AST a little above range, ALT normal and no obvious reason. A doctor would ask about exercise, medicines and recent illness, then repeat the test to see whether the figure settles. One small rise by itself tells a doctor very little.
Add ALT (£39.38) and gamma GT (£36.25) to the repeat, so the liver side is covered in the same draw. If the figure stays up, a GP appointment at Medical Express Clinic costs £150, and a doctor to go through results can arrange any further tests.
What it costs: AST alone or the liver function test
The AST test on its own is £39.38, plus the £50 draw, so £89.38 in total.
The liver function test already includes AST. It measures eight markers, including ALT, gamma GT and AST, for £72.50 plus the same single £50 draw, so £122.50 in total. That is £33.12 more than AST alone, and it covers the other seven markers. AST, ALT and gamma GT as three separate tests would cost £165.01 with the draw, so the panel is the better value if you want the liver side covered. Creatine kinase is not part of the panel, but it can join the same draw.
Blood London is open at 117a Harley Street Monday to Friday 09:00 to 18:00 and Saturday and Sunday 10:00 to 14:00, and you can walk in any day. The optional doctor review is £75.
Common questions
Is AST the same as SGOT?
Yes. SGOT is the older name for the same enzyme, and our test page lists it as AST (SGOT). A lab report may show either.
Do I need to fast?
The liver function test lists no fasting requirement. Follow any instruction your own doctor has given you.
To check your liver or any other part of your health, our private blood tests in London run seven days a week. Walk in, or book online.