Moderate
Amlodipine × diltiazem
Calcium channel blockers (dihydropyridines)×Calcium channel blocker, non-DHP (benzothiazepine derivative)
Mechanism
Dual calcium channel blockade: amlodipine (dihydropyridine), diltiazem (non-dihydropyridine). Additive vasodilation, oedema. Sometimes used in refractory hypertension under cardiology supervision.
Symptoms
Lower blood pressure, postural dizziness, fatigue. Older patients: fall risk.
Management
Avoid in routine practice. Alternative for refractory hypertension: triple therapy amlodipine + ARB + diuretic. If unavoidable: monitor pulse, blood pressure, ECG.