Gout: Two Completely Different Jobs for the Drugs
Gout is caused by needle-sharp uric acid crystals forming in a joint, triggering agonising attacks. The single most important idea in treating it is that the drugs split into two opposite camps — those that calm an acute attack and those that prevent future ones — and giving the wrong type at the wrong time can make things dramatically worse.
Gout is one of the oldest recognised diseases, and its mechanism is vivid. Uric acid is a waste product of the body's normal breakdown of certain molecules (purines). Normally it dissolves in the blood and is passed out by the kidneys. But if the level rises too high, uric acid can crystallise — forming tiny, needle-sharp crystals that lodge in a joint, classically the base of the big toe. The immune system attacks these crystals, producing a sudden, intensely painful, red, hot, swollen joint: an acute gout attack. Over the long term, persistently high uric acid causes repeated attacks and can build up lumpy deposits (tophi). The whole of gout treatment flows from one crucial distinction: are you fighting the fire that's burning right now, or preventing the next one?
The acute attack: calm the inflammation
During an attack, treat the inflammation — not the uric acid level. When a patient has an acute gout attack, the goal is simply to switch off the painful inflammation as fast as possible. Three options do this: NSAIDs (anti-inflammatory painkillers, a fast first choice), colchicine (an older drug that specifically dampens the immune cells attacking the crystals; its main side effect is diarrhoea), and corticosteroids (used when NSAIDs and colchicine can't be, drawing on the steroid anti-inflammatory power from earlier). Here is the single most important rule in gout, and a classic exam trap: during an acute attack, you do NOT start a drug that lowers uric acid. It seems logical to attack the cause, but suddenly changing the uric acid level actually destabilises the crystals and can prolong or worsen the attack. So the acute phase is about calming inflammation only. Fight the fire first; don't start rebuilding the house while it's still burning.
Prevention: lower the uric acid, but start gently
Once an attack has fully settled, the long-term goal is to prevent future attacks by lowering the uric acid level for good. The first-line drug is allopurinol, which blocks the enzyme (xanthine oxidase) that produces uric acid, so less is made and the level slowly falls below the crystallising point. (Febuxostat works the same way as an alternative.) But there's a beautiful piece of counter-intuition here: starting a uric-acid-lowering drug can itself TRIGGER an attack, because dropping the level unsettles existing crystals. This is why two rules apply. First, never start allopurinol during an acute attack — wait until things have calmed. Second, when you do start it, cover the patient for the first weeks or months with a low dose of colchicine or an NSAID to prevent the attacks that the falling uric acid might otherwise provoke. A neat cross-link to remember: allopurinol and its enzyme also affect the breakdown of certain other drugs (like azathioprine), a dangerous interaction. Prevent, but start low and slow with cover — the same theme of respecting the crystals that runs through all of gout.
- Gout = uric acid crystals in a joint → sudden red, hot, painful swelling (classically big toe).
- Acute attack: calm inflammation with NSAIDs, colchicine, or corticosteroids.
- NEVER start a uric-acid-lowering drug during an acute attack — it can worsen/prolong it.
- Prevention: allopurinol (blocks uric acid production) lowers the level long-term.
- Starting allopurinol can trigger an attack — begin low with colchicine/NSAID cover; beware azathioprine interaction.
The whole of gout hinges on one apparent paradox: the drug that treats the CAUSE can trigger the DISEASE if used at the wrong moment. It seems obvious that lowering uric acid should help a gout attack — but rapidly changing the uric acid level, in either direction, unsettles the existing crystals and inflames the joint further. So during an attack you deliberately ignore the uric acid and just fight the inflammation; only once things are calm do you start lowering the level, and even then you start low and add anti-inflammatory cover to ride out the wobble. Timing, not just drug choice, is everything. Get the sequence wrong and you make the very disease you're trying to cure worse — one of medicine's clearest lessons that WHEN you give a drug matters as much as WHICH.
- Starting allopurinol during an acute attack — can worsen and prolong it.
- Stopping allopurinol during an attack in someone already established on it — just continue it.
- Starting allopurinol without anti-inflammatory cover — the falling urate can trigger attacks.
- Combining allopurinol with azathioprine without dose adjustment — dangerous interaction.
A patient is having an acute gout attack. Which is the correct approach?
- Gout = uric acid crystals inflaming a joint (classically the big toe).
- Acute attack: NSAIDs, colchicine or steroids — treat inflammation only.
- Never start uric-acid-lowering drugs mid-attack — it can worsen things.
- Prevent with allopurinol once calm — start low, with anti-inflammatory cover; beware azathioprine.
- Katzung BG. Basic & Clinical Pharmacology — Drugs Used in Gout.
- Brunton LL, et al. Goodman & Gilman's The Pharmacological Basis of Therapeutics — Treatment of gout.
- ACR / EULAR — Guidelines for the management of gout.
- Whalen K. Lippincott Illustrated Reviews: Pharmacology — Drugs for gout.
