Makindo Medical Notes

🚫 Drugs to Avoid in Acute Renal Failure: In patients with renal failure, certain drugs can accumulate to toxic levels or further impair renal function. Awareness of these medicines is crucial for safe prescribing.

⚠️ NSAIDs

• Examples: Ibuprofen, Naproxen, Diclofenac
• Why Avoid: Inhibit prostaglandins → ↓ renal blood flow → ↑ risk of AKI.
• Alternative: Paracetamol for pain relief.

⚠️ ACE Inhibitors & ARBs

• Examples: Lisinopril, Ramipril, Losartan, Valsartan
• Why Avoid: ↓ glomerular filtration pressure → worsening renal function, hyperkalaemia.
• Alternative: May still be used in HF/HTN but with dose reduction & close monitoring.

⚠️ Metformin

• Why Avoid: Risk of lactic acidosis in renal impairment.
• Alternative: Insulin or adjusted-dose sulfonylureas.

⚠️ Potassium-Sparing Diuretics

• Examples: Spironolactone, Amiloride, Triamterene
• Why Avoid: Can cause severe hyperkalaemia.
• Alternative: Loop diuretics (e.g. furosemide) – still monitor electrolytes.

⚠️ Certain Antibiotics

• Examples: Gentamicin, Vancomycin, Nitrofurantoin, Tetracyclines
• Why Avoid: Aminoglycosides are nephrotoxic; nitrofurantoin ineffective/toxic in low eGFR.
• Alternative: Choose antibiotics with renal dose adjustment (per BNF/local guidance).

⚠️ Opiates (Morphine & Codeine)

• Why Avoid: Accumulate → ↑ sedation, respiratory depression, neurotoxicity.
• Alternative: Fentanyl or hydromorphone (safer in renal impairment).

⚠️ Digoxin

• Why Avoid: Narrow therapeutic index, renally cleared → toxicity (arrhythmias, GI upset).
• Alternative: Lower dose + serum level monitoring if essential.

⚠️ Bisphosphonates

• Examples: Alendronate, Risedronate
• Why Avoid: Accumulate and may worsen renal function at CrCl <30 mL/min.
• Alternative: Denosumab (with monitoring).

⚠️ High-Dose Statins

• Examples: High-dose Atorvastatin, Rosuvastatin
• Why Avoid: ↑ risk of rhabdomyolysis → AKI.
• Alternative: Lower doses, or non-statin lipid-lowering drugs if required.

📋 Summary Table

Drug/Class	Risk in Renal Failure
NSAIDs	Nephrotoxic, ↓ GFR
ACEI/ARBs	Worsen renal function, hyperkalaemia
Metformin	Lactic acidosis
K-sparing diuretics	Hyperkalaemia
Aminoglycosides, Vancomycin	Nephrotoxic
Morphine, Codeine	Neurotoxicity, sedation
Digoxin	Accumulates → arrhythmias
Lithium	Toxicity → arrhythmias, seizures
Bisphosphonates	Contraindicated if CrCl <30
High-dose Statins	Rhabdomyolysis → AKI
Amphotericin B, Tacrolimus, Ciclosporin	Nephrotoxic immunosuppressants/antifungals
Methotrexate, Aciclovir	Precipitate in tubules → nephrotoxic

📚 References

• National Kidney Foundation
• British National Formulary (BNF)