Starting Allopurinol During Acute Gout
Allopurinol can be started during an acute gout attack, provided effective anti-inflammatory treatment is already established. 1, 2
Key Requirements Before Initiating
When starting allopurinol during an acute flare, you must ensure:
- Effective anti-inflammatory therapy is established first with NSAIDs, colchicine, or corticosteroids 2, 3
- Prophylactic colchicine 0.5-1 mg daily must be started simultaneously and continued for at least 3-6 months (not <3 months) 1, 2, 3
- Start at a low dose of 100 mg daily (or 50 mg daily if CKD stage 4 or worse) 1, 4, 3
Evidence Supporting This Approach
The 2020 American College of Rheumatology guidelines conditionally recommend starting urate-lowering therapy during a gout flare rather than waiting for the flare to resolve. 1 This represents a shift from traditional teaching that avoided allopurinol initiation during acute attacks.
Two randomized controlled trials directly tested this question:
- A 2015 study of 31 patients found no significant difference in days to resolution (15.4 days with allopurinol vs 13.4 days with placebo, P=0.5) when starting allopurinol at 100 mg daily during acute attacks 5
- A 2012 trial of 57 patients showed no difference in daily pain scores or subsequent flares when initiating allopurinol 300 mg daily versus placebo during acute attacks 6
Both studies demonstrate that starting allopurinol during an acute attack does not prolong the attack or worsen pain when appropriate anti-inflammatory therapy is used. 5, 6
Dosing Strategy
Start low and titrate slowly:
- Begin at 100 mg daily (50 mg if severe CKD) 1, 4, 3
- Increase by 100 mg every 2-4 weeks based on serum uric acid monitoring 1, 4, 3
- Target serum uric acid <6 mg/dL (or <5 mg/dL for severe gout with tophi) 1, 4
- Maximum dose is 800 mg daily 3
Critical Pitfalls to Avoid
Starting without prophylaxis: This dramatically increases the risk of triggering additional acute attacks during the first months of therapy. 1, 2, 3 The FDA label explicitly states that "maintenance doses of colchicine generally should be given prophylactically when allopurinol tablets are begun." 3
Using too high a starting dose: Starting above 100 mg daily increases the risk of precipitating flares and hypersensitivity reactions. 2, 3 The rapid reduction in serum uric acid from higher initial doses can mobilize urate from tissue deposits and trigger attacks. 3
Stopping prophylaxis too early: Prophylaxis should continue for at least 6 months, not just 3 months or less. 1, 2 The 2020 ACR guidelines strongly recommend 3-6 months over <3 months. 1
Stopping at 300 mg without checking if target is reached: More than 50% of patients fail to achieve target serum uric acid with ≤300 mg daily. 2, 4 The dose should be titrated upward until the target is reached, not stopped arbitrarily at 300 mg. 4, 3
Practical Implementation
The 2017 EULAR guidelines note that while limited patient numbers in studies don't allow definitive conclusions, the available evidence supports this approach when using standard allopurinol doses (100-300 mg). 2 The key is ensuring adequate anti-inflammatory coverage is in place before initiating urate-lowering therapy. 2, 3
Monitor serum uric acid every 2-5 weeks during titration until target is achieved, then every 6 months. 4 Continue prophylaxis throughout the titration period and for at least 6 months total. 1, 7