Blood pressure lowering efficacy of calcium-channel blockers as second-line therapy for primary hypertension

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: Primary objective: To quantify the additional reduction in systolic blood pressure (SBP) and diastolic blood pressure (DBP) of calcium‐channel blocker (CCB) therapy as a second‐line drug in hypertensive patients. Secondary objectives: 1. To determine the effects of second‐line CCB on variability of blood pressure. 2. To determine the effects of second‐line CCB on pulse pressure. 3. To quantify the effect of second‐line CCB on heart rate. 4. To quantify the effect of second‐line CCB on withdrawals due to adverse effects.