What Happens If You Stop Allopurinol
Stop allopurinol and serum urate returns to its untreated level within weeks. The enzyme it blocks resumes normal function almost as soon as the drug clears, production climbs back, and the blood level is usually back where it started inside a month. Crystal deposits then start rebuilding, and attacks return.
What makes this misleading is the gap. People often feel fine for months after stopping and conclude the gout has resolved. That quiet period is not recovery — it is how long deposits take to regrow to the point of provoking an immune response again.
What the blood level does
Allopurinol inhibits xanthine oxidase, and that inhibition lasts only as long as the drug is present. There is no lasting change to the enzyme and nothing that persists. Humans lack uricase — the enzyme most mammals use to break urate down further — which is why human urate runs high enough to crystallise at all, and why the problem is permanent without treatment.
So a level that had been held below the 6 mg/dL (360 µmol/L) target climbs back towards wherever your untreated baseline sat — 8, 9, sometimes higher (480 to 535 µmol/L and beyond). Above the saturation point of roughly 6.8 mg/dL (about 400 µmol/L), crystals form rather than dissolve. The direction of travel simply reverses.
Why the quiet period is so convincing
If you were on treatment long enough to clear most of your crystal reservoir, there is genuinely less to react to for a while. Attacks need a certain crystal burden in the joint, and rebuilding it takes time — often several months, occasionally longer.
The result is a perfect trap. Someone stops, has no attacks for eight months, and takes that as proof they never needed it. Then the flares return, and the intervening period has been spent redepositing crystals in joints that had been slowly clearing. What happens if gout goes untreated sets out where that road ends — damage, tophi and kidney stones accumulate silently across years.
The thing to hold on to: absence of pain is not the same as absence of disease. Gout is not cured by treatment, it is controlled — very often to zero attacks — and control only lasts while the blood level stays down.
The five reasons people actually stop
None of these is stupid, and each has a real answer — one that involves your prescriber rather than a unilateral decision.
1. The flares early on felt like the drug was failing
Starting urate-lowering therapy commonly triggers flares in the first months, as falling urate causes deposits to shed crystals. It is expected, and it is why prophylaxis is co-prescribed for the early phase. It feels like the opposite of progress, which is why so many people quietly stop around month two — see why allopurinol causes flares at first.
What to do instead: ask about better flare cover. That conversation usually solves the problem without the drug being changed at all.
2. Feeling completely fine
Once urate is at target and deposits have largely cleared, nothing happens. No symptoms, no reminders, and a daily tablet with no perceptible effect begins to feel pointless.
What to do instead: treat the blood test as the feedback the symptoms cannot give you. Ask what your last result was and when the next one is due.
3. A rash — related or not
A rash after starting allopurinol should always be assessed promptly, because a small number of serious hypersensitivity reactions begin that way; fever, mouth ulcers or feeling unwell alongside a rash need urgent attention. This is a genuine situation in which a clinician may stop the drug and switch to an alternative — exactly the sort of decision that belongs with them. Allopurinol side effects covers it in detail.
What also happens is that someone develops an unrelated rash months or years in, stops on their own and never restarts — losing a treatment that was working, for a reaction that had nothing to do with it.
What to do instead: get any rash assessed rather than assessing it yourself. The answer might be to switch drugs, or it might be that allopurinol was never the cause.
4. Cost, supply or repeat prescriptions lapsing
Allopurinol is among the cheapest drugs in common use, but a lapsed repeat, a pharmacy out of stock, a house move or a change of insurance can each interrupt supply — and interruptions become permanent surprisingly easily.
What to do instead: if cost or access is the barrier, say so plainly at the surgery — there are usually options, and nobody can solve a problem they do not know about.
5. Simply forgetting
The most common reason of all, and the least discussed. A once-daily tablet with no immediate effect is easy to miss, and missed days become missed weeks.
What to do instead: tie it to something you already do without fail, and be honest at reviews about doses missed. Adherence and an inadequate dose look identical on a blood test, and the fixes are completely different.
Reasons versus answers
| Why people stop | What is really going on | The conversation to have |
|---|---|---|
| Flares got worse | Expected early effect of deposits dissolving | Flare cover for the first months |
| No symptoms any more | Treatment working, disease still present | When is my next urate test? |
| Developed a rash | Sometimes the drug, sometimes coincidence | Prompt assessment; a switch may be appropriate |
| Prescription lapsed | Administrative, not clinical | Fix the repeat before the supply runs out |
| Forgetting doses | Very common and very fixable | Say so honestly at the review |
When stopping is legitimately on the table
This is not a drug nobody ever comes off. A clinician may review or withdraw it after a serious adverse reaction, when an alternative such as febuxostat suits better (compared here), or during significant changes in kidney function. It is occasionally considered after many years at target with no tophi and no attacks, though the evidence there is weak and urate reliably rises again.
What matters is not whether allopurinol can ever be stopped, but who decides. A planned withdrawal with monitoring and a follow-up urate test is a different thing entirely from quietly running out of tablets. If you want to come off it, raise it — with the person who prescribed it, not instead of them.
If you have already stopped
It is not a failure and it is not irreversible. Deposits regrow slowly, so the sooner this is picked up the less there is to undo. Book the conversation, ask for a urate test to see where you actually are, and raise whatever the original reason was — if nobody addresses it, the same thing happens again.
Do not restart on your own initiative from an old box, particularly if you stopped because of a possible reaction. Restarting after a hypersensitivity reaction can be dangerous.
One safety note
If a joint becomes hot, swollen and intensely painful with fever or a general feeling of being unwell, consider septic arthritis rather than a gout flare. A joint infection is an emergency requiring same-day assessment, whatever your gout history and whatever you are or are not currently taking.
Frequently Asked Questions
How quickly does uric acid rise after stopping allopurinol?
Within days it starts climbing and it typically returns to the untreated baseline within a few weeks. There is no tapering effect and no lasting benefit from the months you took it.
I stopped a year ago and feel fine — do I still have gout?
Almost certainly yes, unless your urate has fallen for another reason. A blood test settles it, and a level above target means crystals are being laid down whether or not you can feel it.
Can I take a break from allopurinol over a holiday?
Short gaps let urate rise and can provoke a flare on a trip, which is the opposite of what you want. If something about the routine is awkward, work it out with your prescriber beforehand.
What to read next
- Allopurinol for Gout: A Practical Guide
- Allopurinol Side Effects: An Honest Look
- What Happens If Gout Goes Untreated
- The Uric Acid Target That Actually Matters
- Can Gout Be Cured? What “Gout-Free” Really Means
