What is the best pain medication for extreme renal colic?

Best Pain Medication for Extreme Renal Colic

NSAIDs are strongly recommended as the first-line treatment for extreme renal colic pain, with diclofenac 75mg intramuscularly being the preferred initial option due to superior efficacy compared to opioids. 1

First-Line Treatment: NSAIDs

Diclofenac

• First choice: Diclofenac 75mg intramuscularly for severe pain
• For moderate pain or follow-up therapy: Oral diclofenac 50mg initially, then 50mg every 8 hours as needed 1
• Provides more effective and sustained pain relief than opioids
• Results in less need for rescue analgesia and lower rates of vomiting 1

Alternative NSAIDs (if diclofenac is contraindicated or unavailable)

• Ibuprofen (IV formulation may be more effective than ketorolac) 1, 2
• Ketoprofen
• Ketorolac: 30mg IV or IM for patients <65 years; 15mg IV or IM for patients ≥65 years or with renal impairment 3
  • Onset of action: ~30 minutes
  • Maximum effect: 1-2 hours
  • Duration: 4-6 hours 3

Second-Line Treatment: Opioids

When NSAIDs are contraindicated (severe renal impairment, heart failure, pregnancy, history of peptic ulcer disease, or cardiovascular disease):

• Opioids with an antiemetic 1
• Preferred options for patients with kidney disease:
  • Oxycodone
  • Hydromorphone
  • Fentanyl 1
• Avoid pethidine (meperidine) due to higher rates of vomiting 1, 4

Alternative Option

• Drotaverine 80mg intramuscularly - reported efficacy comparable to diclofenac when NSAIDs are contraindicated 1

Treatment Algorithm

1. Assess for contraindications to NSAIDs:

   • Severe renal impairment
   • Heart failure
   • Pregnancy (especially after 30 weeks)
   • Concurrent use of ACE inhibitors, ARBs, or diuretics
   • History of peptic ulcer disease
   • Cardiovascular disease 1

2. If NO contraindications to NSAIDs:

   • Administer diclofenac 75mg IM as first choice
   • Alternative: Ketorolac 30mg IV/IM (15mg if ≥65 years or renal impairment) 1, 3

3. If contraindications to NSAIDs exist:

   • Administer opioid (oxycodone, hydromorphone, or fentanyl) with an antiemetic
   • Consider drotaverine 80mg IM as an alternative 1

4. For inadequate pain relief after 1 hour:

   • Consider combination therapy (morphine + NSAID may provide greater analgesia than either agent alone in about 10% of patients) 4
   • For breakthrough pain with ketorolac, do not increase dose or frequency; consider supplementing with low-dose opioids "prn" 3

Important Considerations

• Hypovolemia should be corrected prior to administering ketorolac 3
• IV ketorolac must be given over no less than 15 seconds 3
• IM ketorolac should be administered slowly and deeply into the muscle 3
• Ketorolac treatment should not exceed 5 days 3
• Maintain high fluid intake and strain urine to catch any passed calculi 1
• Recent evidence suggests IV ibuprofen may be more effective than IV ketorolac for renal colic pain relief 2

Cautions

• NSAIDs increase risk of functional renal impairment, especially in patients with heart failure, renal artery stenosis, dehydration, renal impairment, or concurrent nephrotoxic drugs 4
• Ketorolac should not be mixed in a small volume with morphine, meperidine, promethazine, or hydroxyzine as this will cause precipitation 3
• For pregnant women, morphine carries a lower risk of adverse effects than NSAIDs 4