Information on the Medication Norvasc

Norvasc is the brand name for a drug called amlodipine besylate, which is a calcium channel blocker (or calcium antagonist). Calcium channel blockers are a type of antihypertensive, meaning they lower blood pressure by relaxing blood vessels, which in turn helps prevent heart attacks, strokes and kidney problems. The FDA approved it in August of 1992, following its approval in other countries as early as January 1990.

How to take Norvasc and Dosages

You can take Norvasc with or without food. The usual dose is a single 5- or 10-mg tablet per day. Be sure your doctor knows about any other blood pressure medication you're taking. If you are taking other blood pressure medications you might be prescribed a single 2.5 mg tablet once per day. The 2.5 mg dose is also prescribed as a starting dosage for the elderly, whose dosage may be elevated to 5 mg if the drug is well tolerated. Your doctor may also prescribe the 2.5 mg dose if you have impaired hepatic (liver) function or if prescribing for a child between 6 and 17 years old. The safety and effectiveness in children under age 6 has not been established so they should not use Norvasc.

Side Effects

Side effects from Norvasc can include swelling and fluid retention, flushing, fatigue, dizziness and a fluttery or throbbing heartbeat (known as palpitations). In clinical trials the side effects most often encountered by users were feet or ankle swelling, tiredness, headache and dizziness. None of these effects were reported by more than 8.4 percent of the test population, and a smaller percentage of users who were taking a placebo also noted these effects.

Contraindications: Who Should Not Take Norvasc

Women who are nursing should not take Norvasc. Pregnant women should not take the drug without thoroughly discussing the possibilities with their physicians. Others who should not take Norvasc include people with impaired liver function, aortic stenosis (an incomplete opening of the aortic valve of the heart) or unstable angina (a type of chest pain caused by lack of oxygen to the heart).

Norvasc Combined With Other Drugs

The 2006 Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) study showed that subjects taking amlodipine and the ACE inhibitor Perindopril were 34 percent less likely to develop diabetes than a group taking a different combination of drugs.
Pfizer, Norvasc's maker, combines it with cholesterol-lowering drug called Lipitor (avorstatin calcium) in a medication called Caduet, The medical rationale for combining the two drugs is that certain populations have both high blood pressure and high cholesterol, as with type 2 diabetics and people with other multiple risk factors. The financial rationale is that the patents have expired on Norvasc while Caduet remains under patent.

Report Side Effects Directly to the FDA

The Food and Drug Administration now maintains a website (see Resources) and a toll-free number where consumers can get information and report problems. Dial (800) FDA-1088 to report problems.