Norvasc (amlodipine besylate) is a leading calcium channel blocker prescription medication specifically formulated for the management of hypertension (high blood pressure) and chronic stable angina. As a first-line therapeutic agent, it functions by relaxing and widening blood vessels, allowing blood to flow more easily and reducing the cardiac workload. Its proven efficacy, favorable safety profile, and once-daily dosing regimen have established it as a cornerstone in cardiovascular treatment protocols worldwide, trusted by clinicians for long-term patient management.

Features

• Active Pharmaceutical Ingredient: Amlodipine besylate.
• Pharmacological Class: Dihydropyridine calcium channel blocker (CCB).
• Available Dosage Strengths: 2.5 mg, 5 mg, and 10 mg oral tablets.
• Standard Dosing Regimen: Once-daily administration.
• Onset of Action: Gradual, with a long elimination half-life of approximately 30–50 hours.
• Bioavailability: 64–90% following oral administration.

Benefits

• Provides consistent 24-hour blood pressure control with a single daily dose, supporting adherence.
• Effectively reduces both systolic and diastolic blood pressure, lowering the risk of heart attack and stroke.
• Improves exercise tolerance and reduces the frequency of angina attacks in patients with coronary artery disease.
• Demonstrates a neutral metabolic profile, making it suitable for use in patients with diabetes or dyslipidemia.
• Offers a generally well-tolerated side effect profile for most patient populations.

Common use

Norvasc is indicated for the first-line treatment of hypertension, either as monotherapy or in combination with other antihypertensive agents such as angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, or thiazide diuretics. It is also indicated for the management of chronic stable angina and vasospastic (Prinzmetal’s) angina. Its mechanism of action, which primarily results in peripheral arterial vasodilation with minimal effects on cardiac conduction, makes it particularly useful for a broad spectrum of patients, including many older adults.

Dosage and direction

The recommended initial adult dosage for hypertension or angina is 5 mg taken orally once daily. This dosage may be decreased to 2.5 mg once daily in patients with hepatic impairment or those who are small, fragile, elderly, or co-administered other antihypertensive agents. Based on the patient’s therapeutic response and tolerability, the dosage can be titrated upward. The maximum recommended daily dose is 10 mg. Doses should be taken at approximately the same time each day, with or without food. The tablet should be swallowed whole with a glass of water. Dose adjustments should be performed gradually, typically at 7- to 14-day intervals.

Precautions

Patients should be monitored for symptoms of hypotension, especially during initial dosage titration or upon increasing the dose. Caution is advised in patients with severe obstructive coronary artery disease, as rapid dosage initiation or increases may rarely exacerbate angina or precipitate an acute myocardial infarction. Although peripheral edema is a common, dose-dependent side effect, its presence should be noted and monitored. Use in patients with severe aortic stenosis requires careful risk-benefit assessment. Patients with hepatic impairment will have significantly increased systemic exposure to amlodipine and require a lower initial dose. Norvasc is not a sublingual medication and is not indicated for the abortive treatment of acute anginal attacks.

Contraindications

Norvasc is contraindicated in patients with a known hypersensitivity to amlodipine or any other dihydropyridine derivatives, or to any of the excipients in the formulation. Its use is also contraindicated in patients with cardiogenic shock, clinically significant aortic stenosis, or unstable angina (except for chronic stable angina). Patients with a history of severe hypotension should not initiate therapy.

Possible side effect

The most common side effect, which is dose-related, is peripheral edema. Other commonly reported adverse reactions include:

• Headache
• Dizziness
• Flushing (feeling of warmth)
• Palpitations
• Fatigue
• Nausea
• Abdominal pain
• Somnolence (drowsiness)

Less frequently, patients may experience:

• Gastrointestinal disturbances (dyspepsia, constipation, diarrhea)
• Gingival hyperplasia
• Asthenia (weakness)
• Muscle cramps
• Tachycardia
• Pruritus (itching), rash

Drug interaction

Norvasc is primarily metabolized by the liver enzyme CYP3A4. Concomitant use with strong or moderate CYP3A4 inhibitors may increase amlodipine plasma concentrations and potentiate its effects, requiring dose monitoring and potential adjustment. Examples include:

• Strong Inhibitors: Ketoconazole, itraconazole, ritonavir.
• Moderate Inhibitors: Diltiazem, verapamil (which is also a calcium channel blocker), erythromycin. Co-administration with other antihypertensive agents will have an additive blood pressure-lowering effect. Use with sildenafil or other phosphodiesterase-5 inhibitors can potentiate the hypotensive effect. Simvastatin co-administration may increase simvastatin systemic exposure; consider limiting the simvastatin dose to 20 mg daily.

Missed dose

If a dose is missed, it should be taken as soon as it is remembered on the same day. If it is almost time for the next scheduled dose, the missed dose should be skipped, and the regular dosing schedule resumed. A double dose should never be taken to make up for a missed one. Maintaining a consistent daily schedule is crucial for stable blood pressure control.

Overdose

Overdosage of Norvasc can be expected to cause profound peripheral vasodilation, leading to marked and potentially symptomatic hypotension and reflex tachycardia. In cases of significant overdose, active cardiovascular support is required, including frequent monitoring of vital signs and elevation of the extremities. Intravenous calcium gluconate may be considered to help reverse the effects of calcium channel blockade. As amlodipine is highly protein-bound, hemodialysis is not likely to be of benefit.

Storage

Store Norvasc tablets at controlled room temperature, 20°C to 25°C (68°F to 77°F), in their original container to protect from light and moisture. Excursions are permitted between 15°C and 30°C (59°F and 86°F). Keep all medications out of the reach of children and pets. Do not use after the expiration date printed on the packaging.

Disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any new treatment. Never disregard professional medical advice or delay in seeking it because of something you have read here.

Reviews

“Norvasc has been a foundational agent in my cardiology practice for over two decades. Its predictable pharmacokinetics and once-daily dosing provide stable 24-hour coverage, which is critical for reducing long-term cardiovascular risk. The side effect profile is generally manageable, with peripheral edema being the most common reason for dose adjustment or switch.” – Cardiologist, 20 years of experience

“In my internal medicine clinic, I find Norvasc to be exceptionally reliable for a wide range of hypertensive patients, particularly the elderly. Its minimal drug interaction profile outside of CYP3A4 inhibitors makes it easy to incorporate into complex polypharmacy regimens. Patient adherence is high due to the simple dosing schedule.” – Internist, 15 years of experience

“As a clinical pharmacist, I appreciate the well-defined pharmacology of amlodipine. Its long half-life not only allows for once-daily dosing but also means a missed dose is less critical than with shorter-acting agents. This provides a buffer for patient non-adherence, which is a common challenge in chronic disease management.” – Clinical Pharmacist, Pharm.D.