Can a patient with an elevated Blood Urea Nitrogen (BUN)/creatinine ratio, indicating impaired renal function, receive a Toradol (ketorolac) shot?

Toradol (Ketorolac) Should NOT Be Given to This Patient

A BUN/creatinine ratio of 44 indicates pre-renal azotemia or volume depletion, and ketorolac is contraindicated in patients with impaired renal function or at high risk for renal decompensation. 1

Why This Patient Is at High Risk

Understanding the BUN/Creatinine Ratio

• A BUN/creatinine ratio >20:1 strongly suggests pre-renal causes such as dehydration or volume depletion 2
• This patient's ratio of 44 is markedly elevated, indicating significant pre-renal azotemia that makes them extremely vulnerable to NSAID-induced acute renal failure 2
• The FDA label explicitly states that ketorolac should be used with caution in patients with impaired renal function, and that patients with underlying renal insufficiency are at increased risk of developing acute renal decompensation or failure 1

Direct FDA Contraindications and Warnings

• The FDA drug label warns that ketorolac is contraindicated in patients with serum creatinine concentrations indicating advanced renal impairment 1
• Ketorolac inhibits prostaglandin-mediated renal vasodilation, which is critical for maintaining renal perfusion in volume-depleted states 1
• In patients with reduced renal perfusion (as indicated by elevated BUN/creatinine ratio), NSAIDs like ketorolac may cause dose-dependent reduction in renal blood flow and precipitate overt renal decompensation 1

Clinical Evidence of Harm

Case Reports Demonstrate Serious Risk

• Multiple case reports document acute renal failure following ketorolac administration, even in patients with initially normal renal function indices 3, 4
• One case described irreversible renal failure in a patient who received ketorolac despite adequate hydration 3
• Elderly patients and those with volume depletion are at particularly high risk for ketorolac-induced acute renal failure 5
• Acute renal failure associated with ketorolac has been documented to occur within 2 days of administration 5

Risk Factors Present in Pre-renal Azotemia

• Volume depletion (indicated by elevated BUN/creatinine ratio) is a well-established risk factor that predisposes patients to NSAID nephrotoxicity 4, 5, 6
• The combination of pre-existing renal hypoperfusion and prostaglandin inhibition creates a dangerous scenario for acute kidney injury 6

What Should Be Done Instead

Immediate Assessment Required

• First, address the underlying cause of the elevated BUN/creatinine ratio before considering any nephrotoxic medications 2
• Assess the patient's volume status and hydration state 7
• If dehydration is present, improvement should be seen within 24-48 hours of adequate fluid repletion 2

Alternative Pain Management

• Consider opioid analgesics instead, which do not carry the same renal risks as NSAIDs 8
• Acetaminophen is another alternative that lacks the nephrotoxic effects of NSAIDs 8

If Renal Function Improves

• Only after the BUN/creatinine ratio normalizes (ideally <20:1) and adequate hydration is confirmed should ketorolac even be reconsidered 2
• Even then, renal function must be very closely monitored if ketorolac is used 3

Critical Pitfall to Avoid

The most dangerous mistake would be administering ketorolac to this patient based solely on a "normal" creatinine level without recognizing that the elevated BUN/creatinine ratio indicates compromised renal perfusion. The FDA explicitly warns that patients with underlying renal insufficiency are at increased risk of developing acute renal decompensation or failure when given ketorolac 1. This patient's markedly elevated ratio of 44 places them in a high-risk category where ketorolac could precipitate irreversible acute renal failure 3, 6.