Amlodipine

Drug Information: Amlodipine

Detailed information regarding Amlodipine, a medication commonly used in clinical settings. Amlodipine is a dihydropyridine calcium channel blocker that selectively inhibits calcium ion influx across cell membranes of cardiac and vascular smooth muscle. This leads to vasodilation, reducing peripheral vascular resistance and lowering blood pressure. It is a long-acting medication, typically administered once daily, making it convenient for patients. Amlodipine is available under various brand names and is frequently prescribed for hypertension and angina.

Category

Antihypertensive

Mechanism of Action

Amlodipine functions as a calcium channel blocker, specifically targeting L-type calcium channels located in vascular smooth muscle and, to a lesser extent, cardiac muscle. These channels are crucial for the influx of calcium ions into cells, a process essential for muscle contraction. By selectively blocking these channels, amlodipine reduces the entry of calcium into vascular smooth muscle cells. This leads to vasodilation, primarily in the peripheral vasculature. This vasodilation reduces peripheral vascular resistance, which in turn lowers blood pressure. Amlodipine’s action is more pronounced on vascular smooth muscle than on cardiac muscle, making it effective in reducing blood pressure without significantly affecting heart rate in most patients. The reduced afterload on the heart also makes it useful in treating certain types of angina. The binding affinity and selectivity of Amlodipine for the L-type calcium channels contribute to its long duration of action, allowing for once-daily dosing.

Clinical Uses

Amlodipine is primarily indicated for the treatment of hypertension, both as monotherapy and in combination with other antihypertensive agents. Its effectiveness in reducing blood pressure makes it a cornerstone in managing patients with essential hypertension. Beyond hypertension, amlodipine is also used in the treatment of chronic stable angina and vasospastic angina (Prinzmetal’s angina). By dilating coronary arteries, amlodipine increases myocardial oxygen supply and reduces the frequency and severity of anginal episodes. It can also be used to reduce the risk of cardiovascular events in patients with coronary artery disease. Studies have shown its efficacy in preventing stroke and heart attack in high-risk hypertensive patients. Amlodipine’s long half-life and consistent effect make it a preferred choice for patients requiring stable blood pressure control throughout the day and night.

Dosage

Adults: The usual starting dose of Amlodipine for hypertension or angina is 5 mg orally once daily. Depending on the patient’s response and tolerance, the dose may be increased to a maximum of 10 mg once daily.

Pediatrics (6-17 years): For pediatric patients, the recommended starting dose is 2.5 mg orally once daily. The dose can be titrated up to 5 mg once daily if blood pressure control is not achieved at the lower dose.

Route of Administration: Oral. Amlodipine can be taken with or without food.

Indications

* Hypertension (high blood pressure)
* Chronic Stable Angina
* Vasospastic Angina (Prinzmetal’s Angina)
* Reducing the risk of cardiovascular events in patients with coronary artery disease.

Contraindications

* Known hypersensitivity to amlodipine or any dihydropyridine calcium channel blocker.
* Severe hypotension.
* Cardiogenic shock.
* Significant aortic stenosis.

FAQ

Q: What is Amlodipine used for?

A: Amlodipine is primarily used to treat high blood pressure (hypertension) and certain types of chest pain (angina).

Q: How quickly does Amlodipine start working?

A: Amlodipine starts to lower blood pressure within a few hours, but it may take a few weeks to reach its full effect.

Q: What are the common side effects of Amlodipine?

A: Common side effects include swelling in the ankles or feet (edema), headache, fatigue, dizziness, and flushing.

Q: Can I stop taking Amlodipine suddenly?

A: It’s important not to stop taking Amlodipine suddenly without consulting your doctor, as it can cause a sudden increase in blood pressure or angina symptoms.

Q: Does Amlodipine interact with other medications?

A: Yes, Amlodipine can interact with several other medications, including some antifungals, antibiotics, and other blood pressure medications. It’s crucial to inform your doctor about all medications you are taking.

Q: Can I drink alcohol while taking Amlodipine?

A: Alcohol can lower blood pressure, and combining it with Amlodipine may increase the risk of dizziness or lightheadedness. It’s best to limit or avoid alcohol consumption while taking this medication.

Q: What should I do if I miss a dose of Amlodipine?

A: If you miss a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose to catch up.

Q: Is Amlodipine safe to take during pregnancy?

A: Amlodipine should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Consult with your doctor for personalized advice.