Kidney Stone Pain Treatment
NSAIDs (diclofenac, ibuprofen, or metamizole) are the definitive first-line treatment for acute kidney stone pain, with intramuscular diclofenac 75 mg providing superior pain relief within 30 minutes compared to opioids. 1, 2, 3
Why NSAIDs Are Superior to Opioids
NSAIDs work by directly decreasing ureteral smooth muscle tone and spasm, addressing the underlying pain mechanism rather than just masking symptoms. 1, 2 This is fundamentally different from opioids, which only provide analgesia without treating the pathophysiology of renal colic.
Key advantages of NSAIDs over opioids:
- Reduce the need for additional analgesia 1
- Lower risk of dependence 4, 2
- Fewer side effects, particularly less vomiting 1
- At least as effective as opioids for kidney stone pain 1
Specific NSAID Recommendations
First-line options include: 1, 3
- Diclofenac 75 mg intramuscularly (strongest evidence)
- Ibuprofen (oral)
- Metamizole (oral)
Use the lowest effective dose to minimize cardiovascular and gastrointestinal risks. 1, 3
When to Use Opioids Instead
Opioids should be reserved as second-choice analgesics only when NSAIDs are contraindicated or ineffective. 1, 4, 2, 3
NSAID contraindications include: 1, 2
- Cardiovascular disease
- Gastrointestinal comorbidities or peptic ulcer risk
- Hypertension
- Renal insufficiency or low glomerular filtration rate 1, 3
- Heart failure
If opioids are required, use: 1, 2
- Hydromorphine
- Pentazocine
- Tramadol
Avoid pethidine due to high rates of vomiting and greater likelihood of requiring additional analgesia. 1
Emergency Situations Requiring Immediate Action
All patients require medical assessment within 30 minutes to exclude life-threatening conditions. 2
Immediate hospital admission is mandatory for: 2
- Shock or fever (sepsis)
- Failure to respond to analgesia within one hour
- Abrupt recurrence of severe pain after initial relief
- Patients over 60 years
- Women with delayed menses
Sepsis with obstructed kidney is a urologic emergency requiring urgent decompression via percutaneous nephrostomy or ureteral stenting—this cannot wait. 1, 2, 3 Definitive stone treatment must be delayed until sepsis is resolved. 1, 3 Urine should be collected for antibiogram testing before and after decompression, and antibiotics administered immediately with regimen adjustment based on culture results. 1, 3
Adjunctive Management for Stone Passage
For stones ≤10 mm without complications, offer observation with medical expulsive therapy (MET) using alpha-blockers such as tamsulosin. 4, 2, 3 The greatest benefit occurs for stones >5 mm in the distal ureter, with stone-free rates of 77.3% versus 54.4% for placebo. 1, 2, 3
Conservative management requires: 3
- Well-controlled pain
- Absence of sepsis
- Adequate renal functional reserve
Maximum duration of conservative treatment is 4-6 weeks from initial presentation. 4, 2, 3 Mandatory periodic imaging is required to monitor stone position and assess for hydronephrosis. 3
Instruct patients to drink fluids targeting urine output of at least 2.5 liters daily to promote stone passage. 2
When Surgical Intervention Is Required
For stones >10 mm, most will require surgical treatment, with ureteroscopy being first-line for distal ureteral stones. 2, 3 For distal stones <10 mm, both ureteroscopy and shock wave lithotripsy are acceptable, though ureteroscopy yields higher stone-free rates with slightly higher complication rates. 3
Common Pitfalls to Avoid
- Do not use opioids as first-line therapy—NSAIDs are superior and avoid dependence risks 1, 4, 2
- Do not delay admission for fever with obstruction—this represents sepsis requiring urgent drainage 2
- Avoid NSAIDs in patients with significantly reduced renal function without careful monitoring 1, 3
- Do not offer prolonged conservative management beyond 6 weeks without reassessment 3