Feline Urate


Often radiolucent, these stones may require a combination of survey and contrast cystography to identify their composition. Stones become more radiodense as their size increases.

General Information

The primary etiology underlying ammonium urate uroliths in most cats is unknown. Although porto-vascular anomalies have been identified in some, this abnormality is uncommon. Small quantities of urate (10% or less) can be admixed with struvite and/or calcium oxalate, and until proven otherwise, is not considered clinically important when developing a prevention plan.


• Serum bile acids to determine if a hepatic shunt is the underlying cause.


• The therapeutic benefit of allopurinol in the management of urate uroliths in cats is unknown. • Potassium citrate if urine pH is consistently ≤6.5 (starting dose: 75mg/kg q12-24h).


• Lower purine/protein foods that produce neutral to alkaline urine (e.g. k/d early support, k/d, others). If needed, feed canned therapeutic foods or add water to achieve a urine specific gravity ≤1.030.


Urinalysis every 3 to 6 months to adjust pH to 6.6 or greater. Medical imaging every 6 to 12 months to detect recurrent stones when small to potentially permit their removal without surgery.


We advise reviewing manufacturer's literature regarding selected therapeutic foods to determine indications and contraindications. For pets with multiple health concerns,we suggest that the selection of diet should take into consideration all health needs of the pet.

Link to Full Recommendation PDF

Feline Urate