What is the recommended dosage of colchicine (Colcrys) for acute gout attacks and prophylaxis?

Colchicine Dosage for Gout

Acute Gout Attack Treatment

For acute gout flares, administer colchicine 1.2 mg at the first sign of symptoms, followed by 0.6 mg one hour later (total 1.8 mg over one hour), but only if treatment can be initiated within 36 hours of symptom onset. 1, 2, 3

Key Dosing Parameters for Acute Treatment:

• Maximum dose: 1.8 mg total over one hour period 3
• Timing is critical: Effectiveness significantly decreases if started beyond 36 hours of symptom onset 1, 2
• Low-dose regimen (1.8 mg total) is equally effective as higher doses with significantly fewer gastrointestinal side effects 1, 2
• After initial loading doses, continue with 0.6 mg once or twice daily (beginning 12 hours after initial doses) until the attack resolves 1, 2

If Patient is Already on Prophylactic Colchicine:

• May administer the acute treatment dose (1.2 mg followed by 0.6 mg one hour later) at first sign of flare 3
• Wait 12 hours after the second acute dose, then resume the prophylactic regimen 2, 3

Prophylaxis Dosing

For prevention of gout flares, the recommended dose is 0.6 mg once or twice daily, with a maximum of 1.2 mg/day. 1, 2, 3

Duration of Prophylaxis:

• Continue for at least 6 months when initiating urate-lowering therapy 1, 2
• Alternative approach: Continue for 3 months after achieving target serum urate if no tophi present, or 6 months if tophi are present 2
• Prophylaxis should be initiated with or just prior to starting urate-lowering therapy (allopurinol, febuxostat, pegloticase) 2, 3

Critical Dose Adjustments

Severe Renal Impairment (eGFR <30 mL/min):

• Avoid colchicine entirely 1, 2
• Use glucocorticoids as first-line treatment instead (prednisone 30-35 mg/day for 3-5 days or intra-articular injection) 2

Moderate Renal Impairment:

• Reduce to single dose of 0.6 mg with no repeat treatment for at least two weeks 1, 2
• For dialysis patients: single 0.6 mg dose, do not repeat before two weeks 2

Drug Interactions Requiring Dose Reduction or Avoidance:

Absolute contraindications (do not use colchicine concurrently): 1, 2, 4

• Strong CYP3A4 and/or P-glycoprotein inhibitors including:

  • Clarithromycin
  • Erythromycin
  • Cyclosporine
  • Ketoconazole/itraconazole
  • Ritonavir/nirmatrelvir (Paxlovid)
  • Verapamil, diltiazem

• Dose reduction required for moderate CYP3A4/P-gp inhibitors 2, 3

• Concurrent statin use increases myopathy risk 4

Common Pitfalls to Avoid

• Starting treatment beyond 36 hours of symptom onset dramatically reduces effectiveness 1, 2
• Not adjusting dose in renal impairment can lead to life-threatening toxicity; colchicine has a narrow therapeutic index with reported fatalities after acute ingestions exceeding 0.5 mg/kg 4
• Failing to screen for drug interactions before prescribing, particularly CYP3A4/P-gp inhibitors 1, 2
• Using colchicine as an analgesic for non-gout pain; it is not an analgesic medication 3
• Discontinuing prophylaxis too early when starting urate-lowering therapy leads to recurrent flares 1

Toxicity Recognition

Colchicine poisoning presents in three phases: 4

1. 10-24 hours: Gastrointestinal symptoms (may mimic gastroenteritis)
2. 24 hours to 7 days: Multi-organ dysfunction, rapidly progressive multi-organ failure and sepsis
3. Recovery phase: Typically within weeks if patient survives

The lowest reported lethal oral doses are 7-26 mg, emphasizing the importance of strict adherence to recommended dosing 4