Gout agents · Pain & inflammation
Colchicine
Colcrys®(brand names vary by market)
Works if you start it early, and poisons you if the kidneys and CYP3A4 are against you.
Mechanism
Binds tubulin and disrupts microtubule assembly, impairing neutrophil chemotaxis and the inflammasome response to urate crystals.
Indications
- Acute gout
- Flare prophylaxis when starting urate-lowering therapy
- Familial Mediterranean fever
- Pericarditis
Formulations
Dosing concepts
Timing is everything
Effective within the first day of a flare and much less so afterwards. Modern low-dose regimens work as well as the old high-dose ones with far less diarrhoea.
Narrow index
Toxicity begins with gastrointestinal symptoms and progresses to marrow suppression and multi-organ failure. There is no antidote.
Concepts, not prescribing instructions. Practice numbers live in current references and local protocols.
Pharmacokinetics
- Bioavailability
- ~45%
- Half-life
- 20 to 40 h, longer in impairment
- Elimination
- mixed: CYP3A4 and P-glycoprotein substrate with biliary and renal elimination: inhibitors of either raise levels sharply
- Protein binding
- ~40%
Adverse effects
- Diarrhoea, nausea, vomitingcommonThe first sign of toxicity as well as the commonest side effect, which makes the distinction important.
- Myopathy and rhabdomyolysisseriousEspecially with statins and in renal impairment.
- Bone marrow suppressionserious
- Peripheral neuropathyserious
Contraindications & precautions
Contraindications
- Concurrent strong CYP3A4 or P-glycoprotein inhibitor in renal or hepatic impairment
- Severe renal impairment with a strong inhibitor
Precautions
- Renal or hepatic impairment
- Concurrent clarithromycin, verapamil, diltiazem, ciclosporin or statins
- Older adults
Interactions
Monitoring
The interacting drug list before every prescription
This is the drug whose fatal cases are nearly all interaction-driven
Renal and hepatic function
They set the safe dose
Diarrhoea
The earliest sign that levels are too high
CBC and CK on prolonged therapy
Marrow and muscle toxicity
Counselling points
- Start it as soon as an attack begins; it works much less well after the first day.
- Diarrhoea means the dose is too high for you. Stop and contact us.
- Tell us before starting any new antibiotic or heart medicine.
- Do not take more than prescribed, ever. There is no antidote for an overdose.
Clinical pearls
- Colchicine plus clarithromycin in a patient with chronic kidney disease has caused deaths. Both drugs are ordinary, both are prescribed casually, and the combination is not.
- Low-dose regimens are as effective as the historical high-dose ones and vastly better tolerated; anyone still describing 'dose to diarrhoea' is quoting obsolete practice.
References & review
- Colchicine product monograph (consult the current version for your market) (monograph)
- Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed. (reference-work)
Last reviewed 2026-08-16 · jurisdiction: global · drug information changes; verify against current references before practice use.