====== Amlodipine ======

Amlodipine is a long-acting [[cardio:ccb:dhp|Dihydropyridine Calcium Channel Blocker]] (DHP CCB).

It primarily causes arterial vasodilation and reduces systemic vascular resistance.

Used in:

  * [[cardio:hypertension:start|Hypertension]]
  * [[cardio:angina:start|Stable Angina]]
  * Vasospastic angina

→ [[cardio:ccb:start|Calcium Channel Blockers]]

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===== Mechanism of Action =====

Amlodipine blocks L-type calcium channels in vascular smooth muscle.

This results in:

  * ↓ Intracellular calcium
  * Arterial vasodilation
  * ↓ Systemic Vascular Resistance (SVR)
  * ↓ Afterload

Minimal direct effect on:

  * SA node
  * AV node
  * Myocardial contractility

Primary action = vascular.

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===== Hemodynamic Effects =====

  * ↓ Blood pressure
  * ↓ Afterload
  * Mild reflex sympathetic activation possible

Does NOT significantly:

  * Slow heart rate
  * Depress AV conduction

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===== Pharmacokinetics =====

Onset:
  * Gradual

Half-life:
  * Long (~30–50 hours)

Dosing:
  * Once daily

Provides smooth 24-hour blood pressure control.

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===== Clinical Use =====

Hypertension:

  * First-line option
  * Often combined with:
      * [[cardio:raas:acei|ACE Inhibitors]]
      * [[cardio:raas:arb|ARBs]]
      * [[cardio:diuretics:thiazide:start|Thiazide Diuretics]]

Stable Angina:

  * Reduces afterload
  * Improves myocardial oxygen balance

Vasospastic Angina:

  * Coronary vasodilation

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===== Adverse Effects =====

Common:

  * Peripheral edema
  * Headache
  * Flushing
  * Gingival hyperplasia

Mechanism of edema:

  * Arteriolar dilation without equivalent venodilation
  * Increased capillary hydrostatic pressure

Edema improves when combined with:

  * [[cardio:raas:acei|ACE Inhibitors]]
  * [[cardio:raas:arb|ARBs]]

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===== Amlodipine vs Non-DHP CCBs =====

Compared to:

  * [[cardio:ccb:verapamil|Verapamil]]
  * [[cardio:ccb:diltiazem|Diltiazem]]

Amlodipine:

  * Does NOT slow AV node
  * Does NOT significantly reduce heart rate
  * Safe in [[cardio:heart_failure:start|HFrEF]] (unlike non-DHP CCBs)

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===== Clinical Pearls =====

  * DHP CCB
  * Potent arterial vasodilator
  * Once-daily dosing
  * Causes peripheral edema
  * Safe in HFrEF
  * Excellent first-line antihypertensive

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===== Related =====

  * [[cardio:ccb:start|Calcium Channel Blockers]]
  * [[cardio:ccb:dhp|Dihydropyridines]]
  * [[cardio:hypertension:start|Hypertension]]
  * [[cardio:angina:start|Anti-Anginal Therapy]]
  * [[cardio:raas:acei|ACE Inhibitors]]