Urolithiasis · House

Red Flags

Obstructing stone with infection (fever, leukocytosis, sepsis) — emergency urgent decompression (ureteric stent or percutaneous nephrostomy) and IV antibiotic; sepsis pathway^[1]
Bilateral obstruction or solitary kidney with obstruction — emergency urology, AKI prevention, decompression^[1]
Pregnancy with renal colic — ultrasound first; non-contrast MRI if needed; conservative management when possible; involve obstetric team^[1]
Recurrent stones, unusual stone composition (struvite, cystine), or family history of stones — full metabolic workup and specialist follow-up^[1]

First-line treatment

Interventions

Acute pain management for renal colic^[1]
NSAID (diclofenac IM 75 mg or IV) is first-line; opioid (morphine 0.1 mg/kg IV) if NSAID contraindicated or insufficient; antiemetic; IV fluid only for dehydration not forced diuresis
Conservative management for uncomplicated stones^[1]
Stones <10 mm without sepsis, intractable pain, or persistent obstruction — observation with hydration, simple analgesia, and medical expulsive therapy; reassess at 4 weeks
Surgical / interventional indications^[1]
Stones >10 mm, persistent obstruction at 4 weeks, recurrent severe pain, infection, or solitary kidney. Options: extracorporeal shock-wave lithotripsy (ESWL), ureteroscopy with laser fragmentation, percutaneous nephrolithotomy (PCNL) for staghorn or large stones
Stone prevention by composition^[1]
Calcium oxalate: hydration to >2.5 L/day urine, dietary calcium normal not low, restrict oxalate and sodium, citrate. Uric acid: alkalinise urine pH 6.5–7, allopurinol if hyperuricaemia. Cystine: hydration, alkalinisation, tiopronin/penicillamine. Struvite: treat infection and remove stone completely

First-line drug therapy

Drug	Class	Adult	Paediatric	Notes
Diclofenac (acute renal colic)^[1]	NSAID	75 mg IM or IV; or 50 mg PO TDS for 24–48 h	1 mg/kg/dose every 8 h	First-line analgesia; faster onset and equal efficacy to opioids; avoid in CKD G3+, peptic ulcer, severe HF, anticoagulation
Tamsulosin (medical expulsive therapy)^[1]	Selective alpha-1A adrenergic blocker	0.4 mg PO daily for up to 4 weeks	—	Improves spontaneous passage of distal ureteric stones >5 mm; reduces analgesia need; orthostatic hypotension; informed consent for off-label use in some jurisdictions
Allopurinol (urate stones / hyperuricosuria)^[1]	Xanthine oxidase inhibitor	100–300 mg PO daily titrated to serum urate <6 mg/dL	10 mg/kg/day	Hyperuricosuria with calcium oxalate or pure uric acid stones; renal dose adjustment; HLA-B*5801 screening in South Asian populations
Potassium citrate (oral chemolysis / hypocitraturia)^[1]	Urinary alkaliniser	10–30 mEq PO TDS targeting urine pH 6.5–7.0	—	Uric acid stones (chemolysis), cystine stones, hypocitraturia; monitor potassium especially with ACEi/ARB; hyperkalaemia risk
Thiazide diuretic (hypercalciuria-driven calcium stones)^[1]	Thiazide diuretic	Hydrochlorothiazide 25 mg PO daily; chlortalidone 12.5–25 mg PO daily; indapamide 1.5 mg PO daily	—	Recurrent calcium stones with hypercalciuria; reduces urinary calcium; check potassium and uric acid

Diclofenac (acute renal colic)^[1]

NSAID

Adult: 75 mg IM or IV; or 50 mg PO TDS for 24–48 h
Paediatric: 1 mg/kg/dose every 8 h

First-line analgesia; faster onset and equal efficacy to opioids; avoid in CKD G3+, peptic ulcer, severe HF, anticoagulation

Tamsulosin (medical expulsive therapy)^[1]

Selective alpha-1A adrenergic blocker

Adult: 0.4 mg PO daily for up to 4 weeks
Paediatric: —

Improves spontaneous passage of distal ureteric stones >5 mm; reduces analgesia need; orthostatic hypotension; informed consent for off-label use in some jurisdictions

Allopurinol (urate stones / hyperuricosuria)^[1]

Xanthine oxidase inhibitor

Adult: 100–300 mg PO daily titrated to serum urate <6 mg/dL
Paediatric: 10 mg/kg/day

Hyperuricosuria with calcium oxalate or pure uric acid stones; renal dose adjustment; HLA-B*5801 screening in South Asian populations

Potassium citrate (oral chemolysis / hypocitraturia)^[1]

Urinary alkaliniser

Adult: 10–30 mEq PO TDS targeting urine pH 6.5–7.0
Paediatric: —

Uric acid stones (chemolysis), cystine stones, hypocitraturia; monitor potassium especially with ACEi/ARB; hyperkalaemia risk

Thiazide diuretic (hypercalciuria-driven calcium stones)^[1]

Thiazide diuretic

Adult: Hydrochlorothiazide 25 mg PO daily; chlortalidone 12.5–25 mg PO daily; indapamide 1.5 mg PO daily
Paediatric: —

Recurrent calcium stones with hypercalciuria; reduces urinary calcium; check potassium and uric acid

Safety-net

Drink 2.5–3 L of fluid (mostly water) per day to keep urine pale and reduce stone recurrence — single most important preventive measure^[1]
Strain urine to capture passed stones for analysis — composition guides prevention^[1]
Severe pain not controlled by analgesia, fever, vomiting, or inability to pass urine — same-day urology assessment^[1]

Referral criteria

Obstructing stone with infection / sepsis or bilateral obstructionEmergency department; urology for urgent decompression^[1]
Persistent obstruction or stone >10 mmUrology for ESWL, ureteroscopy, or PCNL planning^[1]
Recurrent stone formation, unusual composition, or family historyStone clinic for metabolic workup and individualised prevention^[1]
Pregnancy with renal colic or stonesJoint urology and obstetric clinic; conservative management when possible^[1]

Clinical summary

Diagnosis, acute pain control, medical expulsive therapy, and intervention pathway for adults with kidney and ureteric stones.

References

1.EAU Guidelines on Urolithiasis (2024 update); AUA Surgical Management of Stones; KDIGO/INASL kidney stone metabolic workup (2024)