Stones: Non-Surgical Management

Stone Prevention

Dietary recommendations


Calcium balance

Management based on metabolic workup parameters

Dehydration Hypercalcuria Hypercalcemia Hypernatruria Hyperuricosuria Low urinary pH Hypocitraturia Hyperoxaluria Stone composition Other findings Diagnosis Management
Yes - Dehydration Increase fluid intake to 2-3L
No Yes Yes No - CaPhos HyperPTH Resorptive hypercalciuria Parathyroidectomy
No - Hypercalciuria Thiazide diuretic
Yes Hypernatriuria Limit sodium intake
No Yes Yes - Calcium - Hyperuricosuria Hydration
Uric acid
No - Hyperuricosemia Various causes Treat underlying cause
No No Yes - Hypocitraturia KCit supplement
No (increased) - CaPhos Hypokalemia/Hypochloremia Type I RTA KCit + Hydration
No Yes - Hyperoxaluria Limit dietary oxalate
Consider B6 supplement
No Struvite Urease-splitting bacteria UTI/Struvite stones Complete stone removal
Acetohydroxamic acid
Cystine Cystinuria Cystinuria Hydration
Ammonium acid urate Radiolucent Chronic diarrhea Check for chronic diarrhea causes
Xanthine Xanthinuria Check for mutation vs allopurinol use
Hypomagnesiuria - Hypomagnesiuria Magnesium supplements
Calcium Otherwise normal Idiopathic stone formation KCit supplements


Class Mechanism Indication Side effects Dosing
Thiazide diuretics distal tubule calcium resorption, sodium excretion Hypercalciuria, calcium stones Hypokalemia (may need supplements), hyperuricosuria, hypercalcemia, hyperglycemia, hypocitraturia (secondary to intracellular acidosis), tachyphylaxis HCTZ 25mg BID
Chlorthalidone 25mg QD
Indapamide 2.5mg QD
Potassium citrate (KCit) Increases urinary citrate, alkalinizes urine, binds urinary calcium Calcium stones, low urinary citrate, Type I RTA, chronic diarrhea (use liquid form), thiazide-induced hypocitraturia, HU < 500 GI symptoms, hyperK (requires regular monitoring), increased CaPhos risk, wax coating passes in stool 20mg BID-TID
Calcium supplements Prevents oxalate absorption, maintains normocalcemia Hypocalcemia, hyperoxaluria - test on and off supplementation Increases calcium stone risk 500-600mg CaCarb BID
Sodium bicarbonate
Sodium citrate
Increases urinary citrate, alkalinizes urine KCit replacement if hyperkalemia risk Hypernatremia 650-1300 mEq QD-BID
Allopurinol (Zyloprim) Inhibits uric acid production Calcium stones in setting of hyperuricosuria (> 800/day) and normal calcium, do not give for uric acid stones Transaminitis, rash, myalgias
Check baseline and 1mo LFTs
300mg daily
Alpha-mercaptopropionylglycine (Thiola) Inhibits formation of insoluble cystine bond Cystinuria Transaminitis, anemia, asthenia, GI distress, rash 300mg BID, titrate up PRN
Acetohydroxamic acid (Lithostat) Urease inhibitor Struvite stones that cannot be managed surgically Phlebitis/DVT, hemolytic anemia (3-15%), hypercoagulable state, tremor, headache, rash, palpitations, GI distress, alopecia 250mg BID-TID
Magnesium oxide Increases calcium and phosphate solubility Hypomagnesiuria Diarrhea, hypermagnesiuria in renal insufficiency 140gmg QID or 400-500mg BID