Amlodipine

Amlodipine, sold under the brand name Norvasc among others, is a medication used to treat high blood pressure and coronary artery disease. While not typically recommended in heart failure, amlodipine may be used if other medications are not sufficient for treating high blood pressure or heart-related chest pain. It is taken by mouth and has an effect for at least a day. Common side effects include swelling, feeling tired, abdominal pain, and nausea. Serious side effects may include low blood pressure or heart attack. Whether use is safe during pregnancy or breastfeeding is unclear. When used by people with liver problems, and in elderly individuals, doses should be reduced. Amlodipine works partly by increasing the size of arteries. It is a long-acting calcium channel blocker of the dihydropyridine type. Amlodipine was patented in 1982 and approved for medical use in 1990. It is on the World Health Organization's List of Essential Medicines, which lists the most effective and safe medicines needed in a health system. It is available as a generic medication. Wholesale cost in the developing world is US$0.003 to 0.066 per day for a typical dose as of 2015. In the United States, a month's supply costs less than $25. In 2016, it was the 5th most prescribed medication in the United States, with more than 75 million prescriptions. Amlodipine is used in the management of hypertension and coronary artery disease in people with either stable angina (where chest pain occurs mostly after physical or emotional stress) or vasospastic angina (where it occurs in cycles) and without heart failure. It can be used as either monotherapy or combination therapy for the management of hypertension or coronary artery disease. Amlodipine can be administered to adults and children 6–17 years of age. Calcium channel blockers, including amlodipine, may provide greater protection against stroke than other classes of blood pressure-lowering drugs. Amlodipine along with other calcium channel blockers are considered the first choice in the phamacological management of Raynaud's phenomenon. Amlodipine can be given as a combination therapy with a variety of medications: The only absolute contraindication to amlodipine is an allergy to amlodipine or any other dihydropyridines. Other situations occur, however, where amlodipine generally should not be used. In patients with cardiogenic shock, where the heart's ventricles are not able to pump enough blood, calcium channel blockers exacerbate the situation by preventing the flow of calcium ions into cardiac cells, which is required for the heart to pump. While use in patients with aortic stenosis (narrowing of the aorta where it meets the left ventricle) since it does not inhibit the ventricle's function is generally safe, it can still cause collapse in cases of severe stenosis. In unstable angina (excluding variant angina), amlodipine can cause a reflex increase in cardiac contractility (how hard the ventricles squeeze) and heart rate, which together increase the demand for oxygen by the heart itself. Patients with severe hypotension can have their low blood pressure exacerbated, and patients in heart failure can get pulmonary edema. Those with impaired liver function are unable to metabolize amlodipine to its full extent, giving it a longer half-life than typical.