Initial Treatment for Renal Colic

First-Line Analgesic Approach

• The European Association of Urology recommends administering NSAIDs as the primary analgesic because they reduce the need for additional analgesia compared to opioids and provide superior pain control 1
• The European Urology guideline suggests that intramuscular diclofenac 75 mg is the preferred agent and route due to rapid onset and reliability, with oral and rectal routes being unreliable in acute settings 1
• Alternative NSAIDs include ibuprofen and metamizole, though diclofenac has the strongest evidence base 1

Second-Line Treatment When NSAIDs Are Contraindicated

• The European Urology guideline recommends using opioids only when NSAIDs cannot be given due to contraindications such as renal impairment, cardiovascular disease, gastrointestinal bleeding history, or pregnancy 1
• The European Urology guideline suggests avoiding pethidine as it has the highest rate of vomiting and need for additional analgesia; prefer hydromorphine, pentazocine, or tramadol 1
• In renal impairment, the European Urology guideline recommends using fentanyl because it does not accumulate active metabolites, and avoid morphine, codeine, or tramadol 1

Critical Monitoring and Failure Criteria

• The European Urology guideline recommends that if pain is not controlled within 60 minutes of appropriate analgesia, immediate hospital admission is required 1

Red Flags Requiring Urgent Intervention

• The European Association of Urology recommends that sepsis and/or anuria in an obstructed kidney requires urgent decompression via percutaneous nephrostomy or ureteral stenting 1

Adjunctive Therapies

• The European Association of Urology strongly recommends medical expulsive therapy with alpha-blockers (tamsulosin) for stones >5 mm in the distal ureter to facilitate spontaneous passage 1

Important Caveats and Pitfalls

• The European Urology guideline warns that NSAIDs may impact renal function in patients with low glomerular filtration rate, so use the lowest effective dose and monitor carefully 1
• The European Urology guideline cautions that NSAIDs increase cardiovascular and gastrointestinal risks, particularly in elderly patients with comorbidities 1

Analgesic Management of Suspected Renal Colic

First‑line NSA ID Therapy

• Intramuscular diclofenac 75 mg is the preferred first‑line analgesic for acute renal colic, delivering rapid pain relief within 30 minutes and maintaining adequate control for at least 6 hours; this recommendation carries Grade A evidence and is endorsed by the European Association of Urology. 2
• The European Association of Urology and BMJ guidelines designate IM diclofenac 75 mg as the gold‑standard analgesic for renal colic. 3
• The IM route is specifically favoured because oral and rectal administration are unreliable in the acute setting and IV delivery may be impractical. 3

Contraindications & Alternative Analgesia

• Known NSAID or salicylate allergy constitutes a contraindication to diclofenac use. 4
• When any NSAID contraindication exists, an opioid (e.g., morphine or fentanyl) combined with an anti‑emetic such as cyclizine should be administered. 5

Assessment & Monitoring

• After IM diclofenac administration, pain should be reassessed at 60 minutes to confirm adequate relief. 4
• If analgesia has not succeeded by 60 minutes, immediate hospital admission is required. 2

Red‑Flag Criteria & Admission Triggers

• Failure of analgesia within 60 minutes mandates admission. 4
• Patients older than 60 years should be evaluated for a possible leaking abdominal aortic aneurysm. 6
• Women with a delayed menstrual period should be assessed for ectopic pregnancy. 6

Follow‑up Care

• A telephone follow‑up at 1 hour after the initial assessment is recommended to verify pain control. 4
• Patients should be advised to maintain high fluid intake and to strain their urine to facilitate stone passage. 4
• Fast‑track renal imaging should be arranged within 7 days of presentation. 4