Amlodipine is a slow-channel dihydropyridine calcium agonist. The drug works by blocking the influx of calcium across cell membranes, primarily into vascular smooth muscle and cardiac muscle.1 The contractile processes of vascular smooth muscle and cardiac muscle are dependent the transports of calcium ions into these cells. By widening blood vessels, the drug lowers blood pressure, increases blood flow to the heart, and relieves pain due to angina. Amlodipine is used to treat hypertension, chronic stable angina, and vasospastic angina.
Angina: Amlodipine is used to treat chronic stable and vasospastic (Prinzmetal’s/variant) angina by relaxing and widening blood vessels, increasing blood flow, and suppressing spasms in cardiac muscle. The drug may be given alone or in conjunction with other anti-angina medications.
Hypertension: Amlodipine’s vasodilation properties make the drug suitable for treating hypertension. The drug may be given alone or in conjunction with other antihypertensive medications.
Coronary Artery Disease: Amlodipine has been shown to reduce the risk of hospitalization due to angina and the risk of coronary revascularization procedures in patients who have recent angiograms documenting coronary artery disease, and who have not suffered heart failure or an ejection fraction lower than 40%.2
Side Effects and Drug Interactions
Common side effects in patients taking amlodipine include3:
Drowsiness or fatigue
Patients who suffer from severity of these common side effects should contact their pharmacist or physician right away. Patients who experience an allergic reaction (hives, trouble breathing, swelling of the face, lips, tongue, or throat) or the feeling of imminent fainting, swelling, swelling of the hands, ankles, or feet, pounding heartbeats, fluttering in the chest, chest pain, heaviness on the chest, pain that spreads from the chest to the arm or shoulder, nausea, sweating, or general malaise should contact their physician immediately.
Patients who are allergic to amlodipine should not take this drug. This drug may cause a worsening of angina, myocardial infarct, or hypotension.4 Patients who are at risk for these conditions should advise their physician. This drug is heavily metabolized in the liver and may not be advised for patients who have impaired liver function. Amlodipine has not been studied well in pregnant or nursing patients, and patients who are under six years of age.
Latest News and Research
Studies investigating the full therapeutic effects of amlodipine on a patient’s cardiovascular system are ongoing. Based on angiographic studies, it has been postulated that calcium channel-blockers may prevent the formation of new coronary lesions, the progression of small lesions, or both.5 One study found that although amlodipine had no significant effect on the progression of coronary atherosclerosis or the risk of a major cardiovascular event, the drug was associated with fewer hospitalizations due to unstable angina and revascularization. Another study found that combination therapy with both atorvastatin and amlodipine in hypertensive patients was associated with a higher reduction in cardiovascular risks and cardiovascular-related death.6
A number of studies are also ongoing in determining how amlodipine affects different populations. For example, in a general community population amlodipine showed a similar safety and efficacy profile in treating mild to moderate hypertension across the board. However, a subset analysis showed that women had a greater blood pressure response to the drug.7 Similarly, amlodipine was found to have no significant therapeutic and safety differences between black and non-black communities.8 However, in a different study, it was observed that black patients initially saw better stroke outcomes with amlodipine over chlorthalidone and lisinopril.9