Minor
Amlodipine × Enalapril
Calcium channel blockers (dihydropyridines)×Angiotensin-converting enzyme inhibitors (ACEi)
Mechanism
Target combination in hypertension: synergistic BP lowering via different mechanisms (calcium channel blockade plus RAAS suppression). Amlodipine partly offsets peripheral oedema via arteriolar vasodilation; enalapril balances it through venular action.
Symptoms
Possible mild leg oedema (mainly from amlodipine) and a rare dry cough (from enalapril). On starting in older patients: dizziness.
Management
Standard fixed combination in hypertension. Start with minimal doses (5 mg + 5 mg) with up-titration every 2–4 weeks. Check creatinine and potassium 1–2 weeks after enalapril start, then every 6 months.
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