Amlodipine

A long-acting calcium channel blocker used to treat high blood pressure and angina.

What is Amlodipine?

Amlodipine is a calcium channel blocker (CCB) belonging to the dihydropyridine class, commonly prescribed for hypertension and angina pectoris.

It relaxes blood vessels, improving blood flow and reducing blood pressure.

History & Background

Amlodipine was developed as a long-acting calcium channel blocker, allowing once-daily dosing with fewer cardiac side effects.

Chemical Structure & Properties

• IUPAC name: 3-ethyl 5-methyl (4RS)-2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-6-methyl-1,4-dihydropyridine-3,5-dicarboxylate
• Molecular formula: C₂₀H₂₅ClN₂O₅
• Molar mass: 408.88 g/mol
• Functional groups: Dihydropyridine, ester, amine

Mechanism of Action

Amlodipine lowers blood pressure by:

• Blocking L-type calcium channels
• Relaxing vascular smooth muscle
• Reducing peripheral vascular resistance

Pharmacokinetics

• Absorption: Well absorbed orally
• Peak plasma time: 6–12 hours
• Half-life: 30–50 hours
• Metabolism: Liver (CYP3A4)
• Excretion: Urine and feces

Medical Uses

• Hypertension
• Chronic stable angina
• Vasospastic (Prinzmetal) angina

Dosage Guidelines

Adults: 5–10 mg once daily

Elderly: Start with 2.5 mg daily

⚠️ Sudden stopping may worsen angina.

Side Effects

• Ankle edema
• Headache
• Flushing
• Dizziness

Warnings & Precautions

• Use cautiously in severe hypotension
• Monitor blood pressure regularly
• Safe in diabetes patients

Drug Interactions

• Grapefruit juice
• Strong CYP3A4 inhibitors
• Other antihypertensive drugs

Frequently Asked Questions

Does amlodipine lower BP? – Yes.

Does it cause cough? – No.

Is it safe long-term? – Yes.

Can it cause swelling? – Yes, ankle edema.

⚠️ Educational content only. Not a substitute for professional medical advice.