Can Amlodipine Lower Heart Rate?
No, amlodipine does not lower heart rate and should not be used to treat tachycardia. 1
Mechanism and Heart Rate Effects
Amlodipine is a dihydropyridine calcium channel blocker that selectively acts on vascular smooth muscle rather than cardiac tissue, producing marked peripheral vasodilation without direct effects on heart rate, contractility, or cardiac conduction. 2, 1
Key Pharmacodynamic Properties:
Amlodipine does not change sinoatrial nodal function or atrioventricular conduction in intact animals or humans, as confirmed by FDA labeling and electrophysiologic studies. 1
Chronic oral administration does not lead to clinically significant changes in heart rate in normotensive patients with angina or hypertensive patients, even though acute IV administration may transiently increase heart rate. 1
In clinical trials with angina patients, amlodipine therapy did not alter electrocardiographic intervals or produce changes in heart rate (+0.3 bpm average change). 1
Comparative Evidence on Heart Rate Effects
Amlodipine vs. Other Dihydropyridines:
A well-designed 1998 comparative study demonstrated critical differences between dihydropyridines with different half-lives. 3
Amlodipine did not change 24-hour average heart rate in hypertensive patients, while nifedipine retard significantly increased heart rate (+3.3 bpm, p<0.05). 3
Amlodipine did not alter autonomic nervous system activity (no change in parasympathetic or sympathetic indices), whereas nifedipine retard decreased parasympathetic activity and increased sympathetic activity with reflex tachycardia. 3
Both agents lowered blood pressure similarly, but only nifedipine caused sympathetic activation. 3
Amlodipine Combined with Beta-Blockers:
When combined with atenolol in angina patients, amlodipine did not change heart rate and had no effect on 24-hour maximum/minimum heart rate or heart rate variability on Holter monitoring. 4
No adverse effects on electrocardiographic parameters were observed when amlodipine was administered with beta-blockers in clinical studies. 1
Clinical Implications for Tachycardia
When Heart Rate Control is Needed:
If you need to lower heart rate in a patient with hypertension or angina, choose a non-dihydropyridine calcium channel blocker (diltiazem or verapamil) or a beta-blocker instead. 2
Non-dihydropyridine calcium channel blockers (diltiazem, verapamil) have direct negative chronotropic and dromotropic effects on cardiac pacemaker and AV conduction cells, effectively lowering heart rate. 2
Beta-blockers should be the preferred treatment in patients with chronic stable angina who have high heart rate, history of supraventricular tachycardia, or hypertrophic cardiomyopathy. 2
When Amlodipine is Appropriate:
Choose amlodipine when the patient has bradycardia or conduction abnormalities (PR >0.24 seconds, AV block), requires concurrent phosphodiesterase-5 inhibitor therapy, or has LV dysfunction/heart failure where non-dihydropyridines are contraindicated. 5
Important Caveats
Reflex tachycardia can occur with short-acting dihydropyridines (immediate-release nifedipine), but amlodipine's long half-life and gradual onset of action minimize this risk. 2, 6, 7
Amlodipine can be safely combined with beta-blockers without causing excessive bradycardia or cardiac block, unlike non-dihydropyridine calcium channel blockers. 8, 5
Do not combine diltiazem or verapamil with ivabradine due to CYP3A4 interactions causing severe bradycardia risk, but amlodipine does not have this interaction concern. 2, 5