The letter from the surgery says your blood test is back. There is a number next to "urate" or "uric acid", maybe flagged high, maybe not. You type it into a search engine at eleven at night and get a dozen different "normal ranges", two different units, and very little about what it means for you. If you live with gout, that number matters. One reading on its own tells you surprisingly little, though. A run of readings over months tells you a lot more.
This guide covers what uric acid is, what the numbers usually mean, why your result can look normal in the middle of a flare, and how keeping your own record makes your next appointment easier.
What uric acid actually is
Uric acid is a normal waste product. Your body makes it when it breaks down purines, which are found in your own cells and in many foods. Most of it is filtered out by the kidneys and leaves in your urine. When the level in your blood stays high for a long time, it can form needle-shaped crystals of monosodium urate in and around joints. Those crystals are what cause gout.
A level that stays high is called hyperuricaemia. It usually comes down to how your kidneys handle uric acid, and that is largely inherited. A 2018 analysis in the BMJ of nearly 17,000 people found that diet explained only a very small share of the differences in uric acid between people, far less than genes did. Gout is not a punishment for how you eat. It is mostly genetics and kidneys.
What is a normal uric acid level?
Two units, one number
In the UK and much of Europe, results are given in micromoles per litre (µmol/L). In the US and some other countries, they use milligrams per decilitre (mg/dL). To convert, 1 mg/dL is roughly 59.5 µmol/L, so 6 mg/dL is about 360 µmol/L.
The lab's reference range
Each laboratory prints its own reference range next to your result, and they differ a little. They tend to be higher for men than for women before the menopause. A typical adult range runs up to somewhere around 400 to 430 µmol/L (about 7 mg/dL) for men and a little lower for women. Always use the range on your own report rather than one from the internet.
Normal is not the same as target
This is the bit that confuses most people. A reference range describes what is common in the general population. It is not the level that is right for someone with gout. Urate crystals start to form once the level goes above roughly 405 µmol/L (6.8 mg/dL). Guidelines therefore aim lower than that for people with gout, so existing crystals can slowly dissolve.
NICE guidance for the UK, published in 2022, suggests a target below 360 µmol/L (6 mg/dL) for most people on urate-lowering treatment. For some people, such as those with tophi (lumps of crystals under the skin) or flares that keep coming, it suggests a lower target of 300 µmol/L (5 mg/dL). Your doctor sets your target. It depends on your history, your kidneys and your other health conditions.
Why your result can look normal during a flare
Uric acid in the blood often drops during a flare, sometimes into the normal range. Part of the reason is that crystals are being deposited in the joint, and part is the body's inflammatory response. So a normal result taken in the middle of a flare does not rule gout out.
NICE advises that if gout is strongly suspected and the level is below 360 µmol/L during a flare, the test should be repeated at least two weeks after the flare has settled. This is one reason it helps to know which of your readings were taken during a flare and which on a quiet day.
High uric acid without gout
Plenty of people have a raised uric acid level and never get gout. A high number on its own is not a diagnosis. Gout is diagnosed from your symptoms and the pattern of your flares, plus the blood test. Sometimes fluid is taken from the joint to look for crystals. Equally, a single high reading does not mean a flare is on its way tomorrow.
Why tracking readings over time matters
If you are on urate-lowering treatment, your doctor will usually check your level more often at first, while things are being adjusted. Once you are at your target, checks are less frequent. NICE suggests a yearly check once things are stable. Between those tests it is easy to lose track. Results arrive by letter, by text, through an app or over the phone, and months later you cannot remember whether 410 was before or after the last change.
A personal record helps you:
- See the direction of travel. Three readings drifting down tell a different story from one good result.
- Put readings next to flares. It is useful to know whether a reading was taken during a flare, just after one, or on a quiet stretch.
- Keep units straight. If you have had tests in different countries or labs, writing down the unit avoids confusion.
- Have a clearer conversation. "My last four results were these, and here is when I had flares" is far easier for a GP or rheumatologist to work with than a memory.
What a blood test number is not
- It is not a verdict on you. Levels are driven mostly by genes and how your kidneys work.
- It is not something to act on alone. Any decision about medicines, including whether to start, stop or change one, belongs with your doctor.
- It is not a substitute for urgent care. A hot, swollen joint with a fever, feeling very unwell, or a joint that was recently injected or operated on needs to be seen today, because a joint infection (septic arthritis) can look exactly like gout. Chest pain or breathlessness is an emergency: call 999.
How GoutMe helps with this
GoutMe is an app for people who live with gout, available on iPhone and Android. It is not a medical device. It does not diagnose or treat anything, and it does not measure your uric acid.
On the Monitor tab there is a Uric acid card. When you get a blood test result, you type in the number and the date. You can use mg/dL or µmol/L, whichever your lab uses. The card shows your latest reading and a graph of your history, so you can see the trend at a glance.
GoutMe does not set a target for you. The screen notes that most guidelines aim under 360 µmol/L (6 mg/dL) and that your doctor sets yours.
You log flares yourself, and starting one takes a single tap. Other things can be tracked in the background if you allow it: sleep and heart rate from a connected watch or health app, and the weather from your phone's location. You do not need a watch. Your uric acid readings and your flare history are kept in the same app.
When it is time for an appointment, the Full Report builds a PDF for a time range you choose. It includes your uric acid readings, your flares, your medicines and more. You bring it to your GP or rheumatologist yourself; nothing is sent automatically.
Find out more at goutme.app.
Sources
- NICE (2022). Gout: diagnosis and management (NG219). National Institute for Health and Care Excellence.
- NHS (2023). Gout. NHS website.
- UK Gout Society. Information about gout and uric acid. UK Gout Society.
- Versus Arthritis. Gout. Versus Arthritis.
- Mayo Clinic. Gout: symptoms and causes. Mayo Foundation for Medical Education and Research.
- Major TJ, Topless RK, Dalbeth N, Merriman TR (2018). Evaluation of the diet wide contribution to serum urate levels: meta-analysis of population based cohorts. BMJ.