Norvasc (Amlodipine): What You Need to Know
Norvasc is a drug that belongs to the family of calcium channel blockers. This group of drugs, also known as calcium antagonists, inhibit the entry of calcium into the arteries and the heart. This produces a relaxing, vasodilatory effect and a reduction in heart rate in between.
Norvasc is the trade name for the active compound amlodipine. It’s also marketed under the generic name or under the brand names Katerzia, Monopina, Istin, and Amlor. It can be used alone or in combination from 6 years of age. Today we’ll show you everything you need to know about it, including side effects.
What is Norvasc used for?
Norvasc is a drug approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA ) to treat high blood pressure, chronic angina pectoris, and vasospastic angina. It can also be used to treat coronary artery disease and heart failure. However, the first three uses are the most common.
In all cases it can be used alone or in combination (with other drugs) and, although it doesn’t cure the disease, it does help to keep it stable and counteract the symptoms. In the case of angina pectoris, amlodipine can’t stop pain symptoms if they have already started, but it can prevent pain in the medium and long term when permanent treatment is started.
Although its use isn’t approved by any of the above agencies, evidence suggests that its use in conjunction with other calcium blockers may be helpful in treating Raynaud’s disease (reducing attacks by up to 33%).
The intake of the drug should only be carried out under the supervision of a specialist. If you suspect that you’re suffering from any of the aforementioned conditions, seek medical assistance to make a diagnostic confirmation. Self-medication is not recommended, especially in scenarios where Norvasc is contraindicated.
Contraindications to treatment with Norvasc
The first contraindication of the drug is hypersensitivity or allergic reactions to its primary component, amlodipine.
Before prescribing it, the specialist must assess both scenarios, or at least follow up during the first days to reduce the dosage or change it to another drug. Other contexts where its use should be avoided are the following:
Pregnancy
Although current studies and research suggest that the risks of taking it are lower than previously believed, the FDA rates Norvasc as a Category C drug for pregnant women. Its administration should be carried out only when the benefits outweigh the risks and always evaluating the reaction each week.
There’s insufficient data to support its use during lactation, so it should also be administered with care after delivery. At certain doses, amlodipine can prolong labor and even pregnancy.
Children under 6 years old
There hasn’t been enough research to recommend taking the drug in children under 6 years of age. Therefore, the side effects or long-term repercussions are unknown if permanent treatment is included. Ideally, research-proven alternatives should be sought or prescribed under strict medical supervision.
Adults over 65
Neither has there been enough research on how the drug works in patients over 65 years of age. Therefore, its administration should be carried out with caution. At the very least, it should start with small doses and then increase according to the patient’s degree of tolerance.
On the other hand, amlodipine can interact with other drugs and thus decrease their effectiveness. If you are following treatment based on pimozide, systemic fusidic acid, bromperidol, abametapir or conivaptan, then you may need to adjust the dose or choose another option.
Side effects of taking Norvasc
Most of the side effects of amlodipine are related to the dose the patient takes. When they do occur, for the most part at least, they do so with low or moderate intensity. The FDA has identified the following side effects:
- General: back pain, malaise, weight gain, and chills.
- Cardiovascular: hypotension, tachycardia, cardiac arrhythmias, bradycardia and vasculitis.
- Peripheral and central nervous system: tremors, vertigo and hypoesthesia.
- Gastrointestinal: anorexia, constipation, diarrhea and vomiting.
- Psychiatric: sleep disorders, depression, anxiety, nervousness, and sexual dysfunction.
- Urinary system: nocturia and other disorders regarding urine frequency.
Other possible side effects are dyspnea, blurred vision, hyperglycemia, sweating, and swelling. Most of these events occur only in 1-2% of the population, although the percentage may be higher depending on the context. If they’re moderate or severe, the specialist should be consulted and they will seek an alternative or adjust the dosage.
Dosage and storage of Norvasc
The drug is marketed in most countries in doses of 2.5, 5, and 10 milligrams. It’s always recommended to start with the smallest dose and then gradually increase over the following weeks until you reach the maximum, if applicable. It’s usually taken once a day, preferably in the morning.
Since there’s no evidence of interaction with food or drink, it isn’t necessary for patients to undergo treatment during fasting. However, it will depend on the specialist’s way of seeing things. If you have forgotten to take it, take it as soon as possible unless there are now fewer than 12 hours before the next dosage.
Don’t stop the medication without doctor supervision, and don’t increase the dosage if you feel the symptoms of the condition are getting worse. Norvasc should be stored in a dry place, at a temperature no lower than 15 degrees Celsius (59 degrees Fahrenheit)
Studies show that plasma concentrations of the drug may be higher where there’s severe liver failure or kidney failure. You must communicate these conditions to the specialist to make a possible dosage adjustment. If you opt for its commercialization in liquid form, remember to shake well before using.
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- Thompson, A. E., & Pope, J. E. Calcium channel blockers for primary Raynaud’s phenomenon: a meta-analysis. Rheumatology. 2005; 44(2): 145-150.