Calcium channel blockers

Synonyms in a broader sense

Calcium channel blockers

English:

antagonist of calcium

definition

Calcium antagonists have an opposite effect to calcium: They prevent calcium from reaching the heart muscle cells, the cells of the electrical conduction system (stimulus conduction system of the heart) on the heart and the muscle cells of the blood vessels.

This group of drugs is used to treat high blood pressure (arterial hypertension), cardiac arrhythmias and damage to the coronary arteries (coronary artery disease) caused by hardening of the arteries (arteriosclerosis).

How do the calcium channel blockers work?

This leads to the heart muscle Lack of calcium to a reduced effectiveness. The pulse or the heartbeat becomes slower because the cells of the stimulus conduction system work more slowly due to the lower amount of calcium. As a result of these effects, the heart is better supplied with oxygen, so that a heart with damaged Coronary arteries in the context of coronary heart disease can be better cared for again.

The blood vessel walls relax increasingly, which is why the resistance in the vessels decreases. The resistance is the pressure exerted by the vessels on the heart Cardiovascular system oppose.

What are the side effects of therapy with calcium channel blockers?

The side effects of the calcium channel blockers of the phenylalkylamine and benzothiazepine types are slow heartbeat and cardiac arrhythmias. During treatment with verapamil, constipation (constipation) can occur.
The use of dihydropyridines can lead to a rapid pulse or heartbeat and water retention (edema) in the legs.
Due to the vasodilating effect, which is common to all calcium channel blockers, headaches, dizziness and a feeling of warmth with reddening of the face are possible.

All three groups of calcium channel blockers can cause allergic reactions to the active ingredient. The drug should then be discontinued immediately!

When should calcium channel blockers not be taken?

Calcium channel blockers should not be given to patients who have had a heart attack less than 6 weeks ago. Likewise, patients with cardiac insufficiency (cardiac insufficiency), with a disturbance in the conduction system of the heart (cardiac arrhythmia) or acute circulatory disorders of the heart must not take calcium channel blockers.
There is a so-called contraindication for this group of drugs for the diseases mentioned as well as during pregnancy, which prohibits the administration of the drug because of serious side effects.

What are the alternatives to calcium channel blockers?

The answer to the question of what the alternatives to calcium channel blockers are depends primarily on the purpose for which the drug is to be taken. When treating high blood pressure, for example, there are several alternatives that can be chosen. In addition to the so-called ACE inhibitors, the thiazides or, if necessary, the beta blockers are also suitable for therapy.

First and foremost, when choosing a suitable medication, the doctor will take into account the circumstances of the patient, such as age and secondary diseases. In some cases, an initially prescribed drug may not be well tolerated. If this is a calcium channel blocker, you can switch to one of the alternative drugs mentioned. In addition, when considering which alternatives to drugs such as calcium channel blockers are available, it should always be taken into account that, in some cases, great progress can also be made with non-drug measures. For example, if the blood pressure is only slightly elevated, a healthy diet and sufficient physical exercise can in many cases lead to an improvement, so that it may even not be necessary to take any medication. In any case, you should discuss the possible alternatives to taking calcium channel blockers with your doctor.

Calcium channel blockers in angina pectoris

Calcium channel blockers are an important ingredient in the treatment of angina pectoris. Usually these are used with another drug to treat the symptoms (chest tightness, shortness of breath and pain when exposed to stress or cold). The doctor also prescribes either a beta blocker or a so-called nitrate. The prescription must be strictly followed, otherwise the wrong combination can worsen the situation. Caution is always advised if the medication no longer works in the event of an angina pectoris attack or if the symptoms occur without or with very little stress. It can then also be the signs of a heart attack that can only be ruled out or treated if necessary in hospital. If you have symptoms, you should immediately notify or consult a doctor.

Calcium channel blockers in Parkinson's disease

Calcium channel blockers should not be used in people with Parkinson's disease. Research has shown that certain representatives of this group of drugs can worsen the symptoms typical of the disease. However, there are also studies that suggest that a certain calcium channel blocker has a positive effect on the course of the disease in Parkinson's disease. Due to this (still) ambiguous study situation, calcium antagonists should generally not be used in people with Parkinson's disease until new research findings are obtained.

Different types of calcium channel blockers

This group of drugs can be divided into three further subgroups, which develop their effect in different places (heart muscle, stimulus conduction system, blood vessels):
The group of Phenylalkylamines, of the Benzothiazepines and the Dihydropyridines.

The groups of Calcium channel blockers:

  • Active substance name Active substance group Place of action Product name
  • Nifedipine Dihydropyridine vessel walls e.g. Adalat®, Aprical®
  • Nitrendipine Dihydropyridine vessel walls e.g. Bayotensin®, Nitrepress®
  • Amlodipine Dihydropyridine vessel walls e.g. Norvasc®, Amlobeta®
  • Felodipine Dihydropyridine vessel walls e.g. Felocor®, Modip®
  • Verapamil Phenylalkylamines heart and vessel walls e.g. Cardioprotect®, Ispotin®
  • Diltiazem Benzothiazepines heart and vessel walls e.g. Dilsal®, Diltiuc®

The column "Name of the preparation" contains the names of the pharmaceutical companies for their drugs with a special active ingredient from the group of calcium antagonists.

Dihydropyridines

The vessel walls are the main site of action for dihydropyridines (DHP):
They reduce the vascular resistance and thus lower the blood pressure. When taking DHP, the heartbeat can become faster (tachycardia) because the nervous system reacts reflexively to the decrease in blood pressure.

Dihydropyridines are mainly used used in the treatment of high blood pressure.

Phenylalkylamines

The subgroup of phenylalkylamines acts both on the heart and on the blood vessels. The heartbeat slows down and the heart beats less. In addition, the resistance of the vessels decreases. Both mechanisms lower the patient's blood pressure. In contrast to the dihydropyridines, the heartbeat does not become faster, as the drug action cancels the reaction of the nervous system.

Phenylalkylamines are used in the treatment of high blood pressure and cardiac arrhythmias.

Benzothiazepines

The benzothiazepines have similar effects to the phenylalkylamines, but they only slightly reduce the heart's beating power.

One advantage of the drug group is that they have no influence on metabolic functions and consequently do not lead to increases or decreases in blood sugar and the like.

Benzothiazepines are used when a patient has abnormal heart rhythms.

ointment

Ointments containing calcium antagonists can be used to relieve pain and discomfort in the area of ​​the anus. Such an ointment can help, for example, with a haemorrhoidal disease (painful blood vessel bulges at the anus) or with an anal fissure (tear in the intestinal mucosa in the anal canal). It works directly on site and prevents cramping of the sphincter, which can otherwise lead to severe pain. The use of an ointment with a calcium antagonist as an active ingredient can be particularly useful after an operation. This leads to a relaxation of the musculature of the sphincter and to an improved blood flow. This also supports the healing process.The ointment is applied around the anus several times a day with a finger. Only about the size of a pea should be used at a time. Overall, the duration of use should be between four and six weeks. The attending physician will provide the precise instructions for use.

Valsartan

The active ingredient valsartan is not a calcium antagonist but a so-called AT1 antagonist. These do not develop their effect by blocking calcium channels on the cells, but by inhibiting the tissue hormone angiotensin. Although calcium also plays an important role in the cells in the mechanism of action of valsartan, it is still a different group of active substances than the calcium channel blockers. Valsartan and the calcium channel blockers have in common that they are both used to treat high blood pressure. Often both drugs are combined so that a lower dosage can be selected. Whether a calcium channel blocker or better valsartan (or other drugs with a similar mechanism of action) is suitable for a patient depends on the accompanying circumstances. Patients who also suffer from arterial occlusive disease of the legs ("intermittent claudication") are more likely to benefit from the effects of a calcium channel blocker. Anyone suffering from diabetes or heart failure should be treated better with valsartan (or another drug from the group of sartans or ACE inhibitors).