Complications of persistent high blood pressure
AMLODIPINE vs NIFEDIPINE
Introduction:
Amlodipine and Nifedipine are medications belonging to the group of calcium channel blockers primarily used to control high blood pressure. The mechanism of action of both the medications is the same. These medicines cause relaxation of the muscles surrounding the blood vessels and muscles of the heart. This mechanism leads to reduction in blood pressure and increase in blood oxygen supply to the heart. Both Amlodipine and Nifedipine are also used to control angina, chest discomfort due to lack of blood supply to the heart.
Difference in uses:
Amlodipine is a long acting calcium channel blocker. By blocking the inflow of calcium into the muscles of the peripheral blood vessels, it causes them to relax reducing the pressure exerted by blood on the walls of the blood vessels. As a result the blood pressure reduces. It is also used to control the chest pain arising from muscle injury resulting from reduced blood supply to the heart. Relaxation of the coronary arteries supplying blood to the heart muscles helps in increasing blood oxygen supply to the heart. However, amlodipine should never be used in ongoing chest pain.
Nifedipine is a short acting calcium channel blocker causing dilatation of the peripheral blood vessels. This mechanism of action, similar to that of amlodipine, helps lower high blood pressure and increase blood supply to the heart muscles. Nifedipine is used for other purposes too such as in pre-term labour and in Raynaud’s phenomenon (discoloration of fingers and toes due to reduced blood supply as a response to cold and emotional stress). Just like amlodipine nifedipine is also never used for ongoing angina.
Difference in precautions:
Amlodipine is contraindicated in patients with unstable angina, those having severe heart disease, liver disease, aortic artery stenosis, in pregnancy, and during breast feeding. It is also important to note that amlodipine can produce side effects such as swellings of hands and feet, fatigue, dizziness, palpitations, stomach pain, headache, nausea, sleepiness etc. it is always important to inform your doctor immediately if any of these or other untoward symptoms arise.
Nifedipine is contraindicated in patients with severe heart disease, kidney or liver disease, heart failure, blockage in digestive tract, history of stomach surgery, lung disease, in pregnancy, and during breast feeding. The side effects caused by nifedipine are headache, nausea, dizziness, heartburn, fast and irregular heartbeat, constipation, swelling of hands and feet etc. It is seen that patients on nifedipine suffer more side effects as compared to those on amlodipine. These symptoms or any other unusual symptoms occurring after starting nifedipine should immediately be brought to the notice of your physician.
Summary:
Amlodipine and Nifedipine both are used to control high blood pressure and angina. The mechanism through which both of these act is the same but while amlodipine is long acting and nifedipine is a short acting medicine. Due to this the doses of each is different which is best decided by the treating physician. Both of these medicines produce side effects that should be carefully watched for so that the physician is informed as soon as possible. Amlodipine is preferred for long term use in controlling high blood pressure since nifedipine is seen to cause more number of side effects.