Table 2.

Suggested experience-based strategy for initiation of antihyperuricemic therapy

Confirmation of diagnosis: detect urate crystals by means of polarization microscopy Two or more gout flares per annum or tophi/joint destruction due to gout attacks Therapeutic advice1: allopurinol 100–300 mg/day2 allopurinol intolerance: consider febuxostat Laboratory monitoring of effectiveness at 6–8 weeks:3 sUr < 0.30 mmol/L, then continue allopurinol sUr > 0.30–0.36 mmol/L, but no further attacks (without colchicine/NSAID/corticosteroids), then continue allopurinol sUr > 0.30 mmol/L plus gout attacks/persistent tophi and uUr > 1.5 mmol/24 hours, go to 5 sUr > 0.30 mmol/L plus gout attacks/persistent tophi with uUr < 1.5 mmol/24 hours, go to 6 Therapeutic advice: increase allopurinol (eg, + 100 mg/day or double the dose); then go to 4. Allopurinol inefficacy at maximum dosage (corrected for renal function): consider febuxostat Therapeutic advice: add uricosuricum, eg, benzbromarone 100 mg/day, or probenecid 500 twice daily; then go to 4 Laboratory monitoring of effectiveness sUr and uUr (possibly pH4) after 6 months: see 5 NB.: when trying to clear tophi, target value is sUr < 0.30 mmol/L

Notes:

¹Subject to motivation and tolerance by patient.

²Subject to calculated creatinine clearance (cCC) > 50 mL/min, if cCC < 50 mL/min, then only increase allopurinol with 100 mg/day. Serum oxipurinol concentrations might be measured in patients with renal insufficiency.

³Target value for sUr ≤ 0.36 mmol/L might be sufficient when there are no further gout attacks despite withdrawing colchicine/NSAID, otherwise lower target value of 0.30 mmol/L.

⁴If experiencing kidney stones or uUr > 6.0 mmol/24 hours and pH < 7.0 consider alkalising with sodium bicarbonate.

Abbreviations: sUr, serum urate; uUr, 24-hour excretion of urate in urine; NSAID, non-steroidal anti-inflammatory drug.