What is the best treatment for acute renal stone pain?

Treatment for Acute Renal Stone Pain

Intramuscular diclofenac 75 mg is the first-line treatment for acute renal colic pain due to its superior efficacy and safety profile compared to opioids. 1

Diagnosis and Initial Assessment

• Diagnosis is based on:

  • Abrupt onset of severe unilateral flank pain radiating into groin or genitals
  • Examination of abdomen to establish site of maximal tenderness
  • Assessment of vital signs to exclude shock and systemic infection 2

• Perform urinalysis:

  • Hematuria supports diagnosis (present in >80% of cases)
  • Consider alternative diagnoses if urinalysis is negative 2, 1

• Red flags requiring immediate hospital referral:

  • Shock
  • Fever
  • Oligoanuria
  • Age over 60 years (consider abdominal aortic aneurysm)
  • Delayed menses in women (consider ectopic pregnancy) 2, 1

Treatment Algorithm

First-Line Treatment

1. Administer intramuscular diclofenac 75 mg 2, 1

   • NSAIDs are superior to opioids for renal colic pain 3, 4
   • NSAIDs directly address the pathophysiological mechanism by reducing prostaglandin production 1
   • Multiple randomized controlled trials show NSAIDs achieve greater pain reduction, decreased need for rescue medications, and fewer vomiting events compared to opioids 5, 4

2. Reassess pain after 60 minutes 2

   • If pain is controlled: continue with oral NSAIDs as needed
   • If pain is not alleviated: arrange immediate hospital admission 2

Alternative Treatment (When NSAIDs are Contraindicated)

• Contraindications to NSAIDs include:

  • Severe renal impairment
  • Heart failure
  • Pregnancy
  • History of peptic ulcer disease
  • Cardiovascular disease 2, 1

• For patients with NSAID contraindications:

  • Use opioids combined with an antiemetic (e.g., morphine sulfate with cyclizine) 2
  • Avoid pethidine due to higher rates of vomiting 4
  • When using morphine, start with 0.1 mg to 0.2 mg per kg IV, administered slowly 6

Post-Treatment Instructions

1. Maintain high fluid intake
2. Void urine into a container or through a strainer to catch any passed calculus
3. Contact doctor if pain worsens or new symptoms develop 2, 1

Follow-up Care

• General practitioner should follow up by phone 1 hour after initial assessment 2
• Fast-track investigation should be initiated within 7 days of symptom onset
• Arrange urgent urology outpatient appointment within 7-14 days if renal imaging shows a problem requiring intervention 2, 1

Important Considerations

• NSAIDs have been consistently shown to be more effective than antispasmodics for renal colic 3
• The combination of NSAIDs and antispasmodics does not provide better pain control than NSAIDs alone 3
• Recent trends show decreased opioid use for renal colic in emergency departments, reflecting improved opioid stewardship 7
• Indomethacin appears less effective than other NSAIDs for renal colic pain 3

Pitfalls to Avoid

1. Delaying analgesia - Pain relief should be provided within 30 minutes of assessment 2
2. Missing serious alternative diagnoses - Always consider abdominal aortic aneurysm in older patients and ectopic pregnancy in women of childbearing age 2
3. Overreliance on opioids - NSAIDs are more effective and have fewer side effects than opioids for renal colic 3, 4
4. Inadequate follow-up - Failure to arrange appropriate imaging and specialist review can lead to missed complications 2, 1