In short
Colchicine settles the inflammation a urate crystal causes. It is not a painkiller, it does not lower uric acid, and it works best when taken within the first hours of an attack. Modern dosing is low; the old practice of taking it until diarrhoea began caused far more harm than it prevented.
Colchicine comes from the autumn crocus and has been used for joint pain for a very long time — descriptions consistent with it go back to antiquity. It remains useful. It is also the gout medicine most often taken wrongly, usually because nobody explained what it is for.
What it actually does
When a urate crystal sits in a joint, white cells arrive and attack it, and the resulting inflammation is the pain. Colchicine interferes with how those white cells move and respond. Less cellular traffic means less inflammation, so the attack settles sooner.
Two consequences follow, and both matter.
It is not a painkiller. It will not take the edge off pain the way paracetamol does. What it does is shorten and blunt the inflammation causing the pain, which takes hours rather than minutes.
It does not lower uric acid at all. Someone taking colchicine every day and nothing else is treating the reaction and leaving the deposits exactly where they are. The urate itself is lowered by allopurinol or febuxostat.
Why timing beats dose
Colchicine works best when it is started early — within the first twelve hours or so of an attack. Started on day three, it is far less impressive, which is why people who keep a supply at home and take it at the first twinge do so much better than people who wait for an appointment.
This is the main argument for having a plan agreed in advance, since attacks reliably begin at night.
Why three days, and not until diarrhoea
Older practice was to repeat colchicine hourly until the pain settled or diarrhoea began. It worked, in the sense that nearly everyone reached the diarrhoea first. People became profoundly dehydrated, and in a few cases far worse.
Comparative work showed that a low dose over a short period is as effective for the attack and much better tolerated. Typical modern practice is a small loading dose followed by a lower dose for a short course — commonly one to three days of treatment, decided by the prescriber. Some people continue a low dose a while longer when attacks are frequent.
The short course is therefore not rationing. It is the dose that was shown to work without making people ill.
The second, quieter use
Most colchicine prescriptions in a rheumatology clinic are not for an attack at all. They are preventive cover.
When urate-lowering treatment begins, attacks become more likely for a few months as deposits break up. A low dose of colchicine taken daily through that period, usually three to six months, substantially reduces them. It is stopped once the urate level is stable at target and attacks have settled.
People sometimes find a daily tablet alongside a new allopurinol prescription confusing, and stop one or the other. Why both are given together explains the reasoning. The one to keep taking, always, is the urate-lowering tablet.
The interactions that genuinely matter
This is the part worth reading twice. Colchicine is cleared by pathways that several common drugs block, and when clearance falls the drug accumulates. Colchicine toxicity is serious.
- Clarithromycin and erythromycin — a frequent and dangerous combination, because clarithromycin is prescribed casually for chest infections.
- Some statins, particularly simvastatin and atorvastatin, raising the risk of muscle damage.
- Ciclosporin, ketoconazole, itraconazole, verapamil and diltiazem.
- Grapefruit juice, which affects the same pathway.
And two conditions change the dose: kidney impairment and liver disease both reduce clearance, and the dose must come down accordingly.
If you are prescribed an antibiotic by another doctor, say that you take colchicine. This is the single most useful sentence in this article.
Side effects
The common ones are digestive: nausea, cramps, and diarrhoea. They are dose-related, which is the main reason modern dosing is low. Diarrhoea is a signal to stop and ask, not to push on.
Less common, and more important: muscle pain or weakness, and effects on blood counts with prolonged use or in people with reduced kidney function. New muscle pain on colchicine — particularly alongside a statin — should be reported rather than endured.
It is also worth knowing that colchicine has a narrow margin between a treatment dose and a toxic one. It is not a medicine to share with a relative who has similar pain, or to take on an old prescription after years.
When colchicine is not the right choice
There are alternatives, and sometimes they are better:
- NSAIDs such as naproxen work well for an attack in people who can take them — that is, without significant kidney disease, heart failure, uncontrolled hypertension, ulcer history or blood thinners.
- Steroids, by mouth for a short course or injected into a single joint, are the usual choice when NSAIDs and colchicine are both unsuitable. An injection into one large joint is quick and avoids a systemic dose.
The first 24 hours of an attack covers how these are chosen between.
Beyond gout
Colchicine is used in a few other settings a rheumatology clinic sees — pericarditis, familial Mediterranean fever, and some presentations of Behçet's disease. The dose and duration are different in each. Nothing in this article transfers to those uses.
Taking it safely, in practice
A few habits prevent almost all of the trouble this medicine causes.
- Keep the prescription current. Colchicine taken from a years-old strip, at a dose nobody has reviewed since your kidney function changed, is how people end up in difficulty.
- Know your dose in writing. Not "take it when it hurts" — the number of tablets, how often, and for how many days.
- Never share it. The margin between a treatment dose and a toxic one is narrow, and it depends on kidney function that differs between people.
- Carry it on holiday if you have recurrent attacks. An attack far from home with no medicine is a miserable few days.
- Mention it at every new prescription, particularly antibiotics and statins.
If kidney function changes, the dose changes. That is worth asking about directly at any review where a creatinine has been measured.
The practical summary
- Start it early in an attack; it loses most of its advantage by day three.
- Take the low dose prescribed. More is not faster.
- Expect it to shorten the attack, not to abolish the pain within the hour.
- Diarrhoea means stop and ask.
- It does nothing about your uric acid level, and does not replace allopurinol or febuxostat.
- Tell any doctor prescribing an antibiotic — especially clarithromycin — that you take it.
If you have recurrent attacks and have never been given a written plan for what to take and when, that is worth sorting out between attacks rather than during one. You can request a callback or book a consultation.
Common questions
Why can you only take colchicine for three days?
Because a low dose over a short course was shown to settle an attack as effectively as the old approach of repeated dosing, with far fewer side effects. The older method usually produced severe diarrhoea and dehydration before it produced pain relief. Longer low-dose courses are used separately as preventive cover when urate-lowering treatment begins.
How long does colchicine take to work for gout?
Hours rather than minutes, and it works best when started within about twelve hours of an attack beginning. It reduces the inflammation causing the pain rather than blocking pain directly, so it is not a substitute for a painkiller in the first hours.
Does colchicine lower uric acid?
No. It has no effect on the uric acid level. It settles the inflammation that crystals provoke. Lowering urate requires allopurinol or febuxostat, and that is what dissolves the deposits over time.
Can I take colchicine every day?
A low daily dose is used deliberately for three to six months when urate-lowering treatment starts, to reduce the attacks that happen as deposits break up. Taking it daily on its own, indefinitely, treats the reaction while leaving the cause untouched — and carries risks, particularly if kidney function falls.
Which medicines should not be taken with colchicine?
Clarithromycin and erythromycin are the most important, because they block colchicine clearance and are commonly prescribed for chest infections. Some statins, ciclosporin, ketoconazole, itraconazole, verapamil, diltiazem and grapefruit juice also matter. Doses must be reduced in kidney or liver impairment.
What should I do if colchicine gives me diarrhoea?
Stop taking it and ask your doctor. Diarrhoea is a dose-related effect and a signal that the dose is too high for you, not a sign the medicine is working. Continuing through it is what caused harm under the older dosing practice.
Sources
- NHS — colchicine www.nhs.uk
- MedlinePlus — colchicine medlineplus.gov
- American College of Rheumatology — gout rheumatology.org
- NIAMS — gout treatment www.niams.nih.gov
This article is general information and does not replace a consultation.