Amlodipine: What Does It Do and Dose Amount?
About 45 percent of the American adult population, or 108 million people, struggle with hypertension, or high blood pressure. This “silent killer” is so named because it is the most common cause of cardiovascular disease-related deaths in the United States, but many people do not know they have it until it is too late because they don’t experience any symptoms. High blood pressure is largely influenced by lifestyle choices, such as diet and exercise, so it is common for physicians to recommend that patients with high blood pressure eat right, exercise more, and reduce stress. However, lifestyle changes aren’t enough to manage high blood pressure for everyone, so some people may require treatment with a blood pressure medication in order to get their blood pressure to a normal level. Amlodipine is a commonly prescribed medication that can help treat high blood pressure.
Amlodipine, the generic name for the brand name drugs Norvasc and Katerzia, belongs to a class of medications called calcium channel blockers as an antihypertensive drug. The medication was first patented in 1982 and was approved for medical use in the United States by the Food and Drug Administration (FDA) in 1990. Amlodipine can be purchased in either its name brand or generic forms in the United States and is available by prescription only.
Amlodipine besylate is primarily used to treat chest pain (angina) and other conditions caused by coronary artery disease or heart disease, and it is also used to treat high blood pressure. The drug can be taken in combination with other medications needed to manage heart conditions. Amlodipine reduces the risk of hospitalization and surgeries caused by chest pain by reducing pain associated with angina, and it reduces the risk associated with a heart attack or stroke caused by high blood pressure when used to treat hypertension.
Angina is the medical term for chest pain, and it generally manifests as pain, pressure, or tightness in the heart muscle cells that may be caused by stress or physical activity, such as walking or exercising. Although angina is normally felt in the vascular smooth muscle in the chest, it can sometimes be experienced as pressure, tightness, or pain felt in other places than the chest, such as the neck, jaw, shoulder, back, or either arm. When experiencing bouts of vasospastic angina or variant angina, some people have symptoms of shortness of breath, sweating, nausea, or lightheadedness, and heartburn. Angina can result from decreased blood flow and oxygen to the heart, which is often caused by atherosclerosis, or narrowing of the blood vessels. If not treated properly, angina can increase the risk of heart attack or heart failure and become life-threatening due to low ejection fraction.
High Blood Pressure
Blood pressure is measured as the force resulting from blood pushing against the walls of the blood vessels as the heart beats. This force is how blood is sent to different areas of the body, delivering oxygen. High blood pressure occurs when the blood consistently pushes against the walls of your blood vessels too forcefully for an extended period of time. Hypertension, or high blood pressure, is considered dangerous because it results in an increased workload for the heart and blood vessels. Over time, the blood vessels and heart work less efficiently and must use more effort to send blood to the tissues and organs, which they need in order to function. High blood pressure can often be controlled with lifestyle changes and medication, but if not carefully managed, hypertension can cause a narrowing of the blood vessels by creating microtears in the walls of the arteries. As the blood vessels become more narrow, blood is further prevented from reaching the extremities, causing blood pressure to continue to rise. Eventually, this can lead to a heart attack (myocardial infarction), stroke, congestive heart failure, and death. The majority of high blood pressure cases have no obvious causes, such as medications or medical conditions, and are primarily influenced by lifestyle factors and genetics. However, medication can help you achieve your blood pressure goals.
How It Works
Amlodipine belongs to a class of medications called calcium channel blockers. Like other medications in its class, amlodipine works by blocking calcium from entering the heart and arteries. Calcium causes the heart and arteries to contract more strongly, which is usually a good thing, but people with high blood pressure and angina experience an increase in symptoms when this occurs. Calcium channel blockers lower blood pressure by blocking calcium from entering the heart and arteries, allowing the blood vessels to relax and open. Some calcium channel blockers, including amlodipine, also slow the heart rate, which helps lower blood pressure further and can control an irregular heart and relieve pain associated with angina.
One of the potential benefits of amlodipine is that it has a long history of use in the United States and has developed a reputation as a reliable, effective drug for treating high blood pressure and angina. Use of amlodipine has several additional benefits:
- Children as young as six can receive treatment for high blood pressure with amlodipine.
- Amlodipine effectively reduces the signs and symptoms of angina and high blood pressure for many patients.
- The drug can be combined with other heart medications in patients who have multiple heart issues to address with a lower risk of drug interactions than other medications.
- The medication can be cut or crushed to make taking it easier for patients who have difficulty swallowing pills.
- Because amlodipine is available in a generic form, the medication is generally affordable and accessible for most patients.
In general, amlodipine is considered a relatively safe medication, but some patients should exercise caution when taking the drug because it can cause adverse events. Although there are many benefits associated with amlodipine, as listed above, taking the medication also poses some risks. Risks associated with amlodipine include:
- Patients with liver problems may not be able to process amlodipine quickly, which can cause the drug to build up in their systems and cause an increased risk of experiencing side effects. Patients with severe liver problems may need to take a lower dosage of the medication.
- Patients with heart problems may experience low blood pressure, increased chest pain, heart palpitations, or a heart attack after starting or increasing their dose of amlodipine. It’s important to discuss any existing heart conditions with your doctor.
Your doctor will determine the right dose of amlodipine for you based on drug information and the condition being treated, your age, and several other factors. When used to treat hypertension in adults, doctors will typically start patients out on an initial dose of 5 mg of amlodipine taken once per day through oral administration. If the patient’s blood pressure is not brought under control within 7 to 14 days, the dose may be increased to a maximum of 10 mg per day as directed by the doctor. When used to treat hypertension in children between the ages of 6 and 17 and seniors over the age of 65, the starting dosage is 2.5 mg taken by mouth once per day. While children can bump up to a 5 mg dose if needed to control high blood pressure, elderly patients process drugs more slowly and should use a lower dosage if possible.
The starting dose of amlodipine when used to treat angina in adults is 5 mg of amlodipine taken once per day, with a maximum dose of 10 mg per day. Amlodipine is not authorized for the treatment of angina in children. Senior citizens over the age of 65 should take 5 mg by mouth once per day for the treatment of angina, as they may process the drug more slowly.
Overall, be sure to follow the medical advice of your doctor including informing them about any missed doses and storing the medication at room temperature.
Side effects associated with amlodipine are categorized as either common or serious. Common side effects associated with amlodipine that usually do not need medical attention include:
- Very fast heart rate (arrhythmia)
- Abnormal muscle movements
- Tiredness or extreme sleepiness
- Swelling of the legs or ankles like angioedemas
- Stomach pain
- Hot or warm feeling in the face/flushing
- Irregular heart rate (arrhythmia or atrial fibrillation)
As long as these common side effects are mild, they should go away within a few days or weeks. If side effects persist or allergic reactions occur, talk to your doctor.
Some side effects of amlodipine do require medical attention. Check with your health care provider immediately if you experience any of the following serious side effects while taking amlodipine:
- Low blood pressure, including:
- Severe dizziness
- Increased chest pain or a heart attack. This side effect can occur when you first begin taking amlodipine or increase your dosage. Symptoms may include:
- Upper body discomfort
- Breaking out in a cold sweat
- NauseaChest pain or discomfort
- Shortness of breath
- Unusual tiredness
Use During Pregnancy and Breastfeeding
The use of amlodipine in pregnant women has not been conclusively studied through clinical trials. It is recommended that the medication be used during pregnancy only when clearly needed and when the benefits outweigh the risks to the unborn baby. If you are pregnant, speak with your doctor about taking amlodipine during pregnancy.
Studies indicate that use of amlodipine while breastfeeding has not caused adverse effects by passing into breast milk, but caution should still be exercised if taking amlodipine while breastfeeding. Nursing mothers should speak to their doctors regarding the use of amlodipine while breastfeeding.
People who are allergic to amlodipine or other calcium channel blockers, including nisoldipine or nifedipine, should not take amlodipine. Make sure your doctor is aware of your complete medical history and any prescription drugs or over-the-counter drugs that you currently take, particularly if you have a history of any of the following:
- Aortic stenosis, a structural heart problem
- Very low blood pressure
- Heart problems
- Renal impairment or liver problems or disease
Taking amlodipine can make you feel dizzy. The use of alcohol or marijuana can increase these feelings because of drug interactions. You should not drive or do anything that requires alertness until you know how amlodipine affects you.