Amlodipine Besylate

Amlodipine Besylate

Amlodipine besylate is a medication used primarily in the management of hypertension and coronary artery disease. It is a long-acting calcium channel blocker of the dihydropyridine type. Amlodipine is effective in reducing blood pressure, preventing angina, and improving exercise tolerance in patients with cardiovascular conditions.

Pharmacology

Amlodipine works by inhibiting the influx of calcium ions into vascular smooth muscle and cardiac muscle. This action results in the relaxation of the smooth muscle, leading to vasodilation and a subsequent decrease in blood pressure. The reduction in peripheral vascular resistance decreases the workload on the heart, which is beneficial in conditions such as angina.

Mechanism of Action

Amlodipine selectively inhibits L-type calcium channels in the cell membranes of cardiac and smooth muscle. By blocking these channels, amlodipine prevents calcium from entering the cells, which is necessary for muscle contraction. This results in the relaxation of the arterial walls, leading to a decrease in blood pressure and an increase in oxygen delivery to the heart muscle.

Pharmacokinetics

Amlodipine has a slow onset of action and a long half-life, which allows for once-daily dosing. It is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring 6-12 hours after oral administration. Amlodipine is extensively metabolized in the liver and excreted in the urine.

Clinical Uses

Amlodipine is indicated for the treatment of:

• Hypertension: It is used to lower high blood pressure, which helps prevent strokes, heart attacks, and kidney problems.
• Angina pectoris: Amlodipine is used to prevent chest pain caused by reduced blood flow to the heart muscle.
• Coronary artery disease: It is used to improve exercise tolerance and reduce the frequency of angina attacks.

Side Effects

Common side effects of amlodipine include:

• Peripheral edema
• Dizziness
• Flushing
• Fatigue
• Palpitations

Serious side effects are rare but may include severe hypotension, worsening of angina, and myocardial infarction.

Contraindications

Amlodipine is contraindicated in patients with known hypersensitivity to amlodipine or any of its components. Caution is advised in patients with severe aortic stenosis, as the reduction in afterload may worsen the condition.

Drug Interactions

Amlodipine may interact with other medications, including:

• Simvastatin: Increased risk of simvastatin toxicity.
• CYP3A4 inhibitors: May increase the plasma concentration of amlodipine.
• Beta-blockers: Additive effects on blood pressure and heart rate.

Also see

• Calcium channel blockers
• Hypertension management
• Coronary artery disease treatment
• Angina pectoris