Is hyoscine (scopolamine) a suitable treatment for a patient with renal colic and potentially impaired renal function?

Hyoscine (Scopolamine) is NOT Recommended for Renal Colic

Hyoscine should not be used as a treatment for renal colic, particularly in patients with renal impairment, as it lacks efficacy for pain control and carries significant contraindications in renal disease. 1, 2

Evidence Against Hyoscine Use

Lack of Efficacy

• Hyoscine (scopolamine) as an antispasmodic has been evaluated in comparative trials and adding it to morphine did not provide additional analgesic benefit for renal colic pain. 2
• NSAIDs are significantly more effective than hyoscine for pain reduction in renal colic (5 comparisons, 196 participants: RR 2.44,95% CI 1.61 to 3.70), meaning patients receiving NSAIDs were 2.44 times more likely to achieve adequate pain relief compared to those receiving hyoscine. 3

Contraindications in Renal Disease

• The FDA drug label explicitly states that hyoscine should be used with caution in patients with renal disease. 1
• The drug is substantially excreted by the kidney, and the risk of toxic reactions is greater in patients with impaired renal function. 1
• Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and monitoring renal function may be useful. 1

Recommended Treatment Approach for Renal Colic

First-Line: NSAIDs

• Diclofenac 75 mg intramuscularly is the first-line treatment of choice for acute renal colic, providing superior pain relief compared to opioids with fewer side effects. 4, 5
• NSAIDs reduce the need for additional analgesia and work by providing analgesia while decreasing ureteral smooth muscle tone and spasm. 5

Critical Screening Before NSAIDs

• Patients with low glomerular filtration rate or renal impairment must be screened carefully before prescribing NSAIDs, as they are contraindicated in these cases. 5
• NSAIDs should be avoided in patients with severe renal impairment, heart failure, or cirrhosis. 6

Second-Line: Opioids (When NSAIDs Contraindicated)

• When NSAIDs are contraindicated or insufficient for pain control, opioids should be used as second-line therapy. 4
• For patients with renal impairment specifically, fentanyl is the preferred opioid as it does not accumulate active metabolites in renal failure. 4
• Alternative opioids include hydromorphone, pentazocine, or tramadol—but avoid pethidine due to higher rates of vomiting. 4, 5
• Never use morphine, codeine, or tramadol as first-line agents in patients with renal failure; always start with lower doses and titrate carefully. 4

Clinical Decision Algorithm

For patients with normal renal function:

• Start with diclofenac 75 mg IM 4, 5
• If inadequate response within 30-60 minutes, add or switch to opioids 5

For patients with renal impairment:

• Avoid NSAIDs entirely 5
• Use fentanyl as the preferred opioid with careful dose titration 4
• Monitor closely for respiratory depression and confusion, particularly in elderly patients 7

Common Pitfalls to Avoid

• Do not use hyoscine/scopolamine for renal colic—it lacks proven efficacy and carries renal contraindications. 1, 2, 3
• Do not use standard opioid dosing protocols for patients with renal failure without downward adjustment. 4
• If severe pain does not remit within one hour of initial treatment, the patient should be admitted to hospital immediately. 4, 5