What is the best pain management approach for patients passing kidney stones?

Best Pain Management for Passing Kidney Stones

NSAIDs are the first-line treatment for acute kidney stone pain due to their superior efficacy, fewer side effects, and lower risk of dependence compared to opioids. For patients with renal colic from kidney stones, NSAIDs should be administered as the primary analgesic unless contraindicated. 1, 2, 3

First-Line Pain Management

• NSAIDs have been demonstrated to be more effective than opioids for kidney stone pain, providing better pain control with fewer adverse effects 1, 4
• Multiple randomized controlled trials show that NSAIDs achieve greater reduction in pain scores, decreased need for rescue medications, and fewer vomiting events compared to opioids 3
• Common NSAID options include diclofenac, ibuprofen, and ketorolac 1, 4
• NSAIDs work by not only providing analgesia but also decreasing ureteral smooth muscle tone and ureteral spasm that cause kidney stone pain 1

Second-Line Pain Management

• Opioids should be reserved as second-choice analgesics when NSAIDs are contraindicated or ineffective 1, 2
• Recent trends show decreasing opioid use in emergency departments for kidney stone management, reflecting improved opioid stewardship 5
• When opioids are necessary, agents other than pethidine are recommended (such as hydromorphone, pentazocine, or tramadol) due to pethidine's higher rate of vomiting and greater likelihood of requiring additional analgesia 1

Medical Expulsive Therapy (MET)

• Alpha-blockers (particularly tamsulosin) should be offered as MET for patients with stones >5 mm in the distal ureter 1, 2
• MET not only facilitates stone passage but also reduces pain and limits the need for analgesics 1
• Alpha-blockers are more effective than calcium channel blockers for MET, with a 29% higher stone passage rate compared to controls 1

Special Considerations

• Patients with chronic kidney disease require careful NSAID use due to increased risk of nephrotoxicity, electrolyte derangements, and worsening of hypertension 6
• For patients unable to tolerate NSAIDs, multimodal approaches may be necessary, though specific alternatives are less well-studied 3
• Regional variations and disparities in pain management have been observed, with Black patients less likely than White patients to receive opioids at discharge 5

Stone-Specific Management

• For uric acid stones, potassium citrate should be offered to raise urinary pH to approximately 6.0, which increases stone solubility 1
• For cystine stones, first-line therapy includes increased fluid intake, restriction of sodium and protein intake, and urinary alkalinization 1
• For calcium stones, thiazide diuretics should be offered to patients with high urinary calcium and recurrent stones 1, 2

Follow-up and Monitoring

• A 24-hour urine specimen should be obtained within six months of initiating treatment to assess response to therapy 1, 2
• Periodic blood testing should be performed to assess for adverse effects in patients on pharmacological therapy 1
• Repeat stone analysis should be obtained when available, especially in patients not responding to treatment 1

Common Pitfalls to Avoid

• Defaulting to opioids as first-line therapy instead of NSAIDs 1, 3
• Not considering NSAID contraindications such as renal insufficiency, heart failure, or risk for peptic ulcer disease 1
• Neglecting to address underlying metabolic abnormalities that contribute to stone formation 2
• Using supplemental calcium rather than dietary calcium, as supplements may increase stone formation risk 1