Moderate
Enalapril × Furosemide
Angiotensin-converting enzyme inhibitors (ACEi)×Loop diuretics
Mechanism
Additive antihypertensive effect; in hypovolaemic patients it can trigger acute kidney injury. The triad of ACE inhibitor + diuretic + NSAID is especially dangerous (the "triple whammy").
Symptoms
Decreased urine output, rising creatinine, oedema, nausea, fatigue. Higher risk in older patients and in dehydration.
Management
On starting the combination, begin enalapril at the lowest dose (2.5 mg). Check creatinine and potassium at 1–2 weeks, then every 3 months. In older patients with acute illness and dehydration, both drugs are temporarily stopped until volume is restored.
Sources
- Lexicomp: Lexicomp Drug Interactions (2024)– Wolters Kluwer Clinical Drug Information, Inc. Lexi-Interact Online, 2024
- Pharmaceutical Press: Stockley's Drug Interactions, 12th edition (2024)– Preston CL (ed.). Stockley's Drug Interactions. 12th ed. London: Pharmaceutical Press; 2024