What is the treatment for renal colic?

Treatment of Renal Colic

The first-line treatment for renal colic is rapid administration of injectable non-steroidal anti-inflammatory drugs (NSAIDs), preferably diclofenac 75 mg intramuscularly, which should provide pain relief within 30 minutes. 1

Initial Assessment and Diagnosis

• Diagnosis is based on the abrupt onset of severe unilateral flank pain radiating into the groin or genitals 1
• Urinalysis should be performed when possible, as haematuria supports the diagnosis in over 80% of cases 1
• Examination must include abdominal assessment to establish the site of maximal tenderness and exclude other conditions like peritonitis 1
• Vital signs should be checked to rule out shock and systemic infection 1
• Patients with shock or fever must be admitted to hospital immediately 1
• Consider alternative diagnoses in patients over 60 years (abdominal aortic aneurysm) or women with delayed menses (ectopic pregnancy) 1

Pain Management Algorithm

First-Line Treatment:

• Administer injectable NSAIDs, preferably diclofenac 75 mg intramuscularly 1
• Intramuscular route is preferred as oral and rectal administration are considered unreliable, and intravenous administration is often impractical in primary care settings 1
• Complete pain control should be maintained for at least six hours 1

Alternative Treatment (When NSAIDs are Contraindicated):

• Use opioid analgesics combined with an antiemetic, such as morphine sulfate and cyclizine 1
• Opioids are the first choice during pregnancy due to teratogenic potential of NSAIDs 2
• NSAIDs should be avoided in patients with renal impairment, heart failure, renal artery stenosis, dehydration, or those on nephrotoxic drugs 3, 4

Combination Therapy:

• The combination of morphine and NSAIDs may provide greater analgesic effect than either agent alone in approximately 10% of patients 4

Hospital Admission Criteria

• Patients failing to respond to analgesia within one hour should be immediately admitted to hospital 1
• Abrupt recurrence of severe pain also warrants immediate admission 1
• If the patient cannot be seen within 30 minutes of presentation, paramedical services should be sent to provide analgesia and transport to an emergency department 1

Home Management

• Patients managed at home should drink plenty of fluids 1
• Patients should void urine into a container or through a tea strainer to catch any calculus for diagnostic purposes 1
• Follow-up should include a telephone call one hour after initial assessment and analgesia administration 1
• Instruct patients to contact their doctor if pain worsens or unexpected symptoms develop 1

Follow-Up Investigations

• Determine if a calculus was identified, its size and location 1
• Assess if intervention is needed for a persistent calculus 1
• Consider alternative diagnoses if no calculus is found 1
• Evaluate the risk of developing further episodes 1

Adjunctive Treatments

• Alpha-blockers like tamsulosin may facilitate stone expulsion by relaxing smooth muscle in the intramural ureteral tract 2
• Local active warming (42°C to the abdomen or lower back) may help reduce pain according to some evidence 4

Common Pitfalls to Avoid

• Do not delay analgesia administration; pain relief should be provided within 30 minutes of assessment 1
• Avoid NSAIDs in pregnant women; use morphine instead 4
• Do not rely solely on the presence or absence of hematuria for diagnosis, as not all patients can provide a specimen 1
• Avoid intensive hydration as it is not currently recommended for acute management 5