Adalat® is a substance that falls into the group of calcium channel blockers. Together with the drug bayotensin, it is one of the most popular representatives of the calcium channel blockers.
- Calcium channel blockers
Of the Active ingredient of Adalat® is Nifedipine. There are a variety of other active ingredients, such as Amlodipine, Felodipine, isradipine, nicardipine, nimodipine, nisoldipine and Nitrendipinethat act similarly to nifedipine and therefore as Nifedipine-type substances are designated.
Mechanism of action
Smooth muscle cells, such as those found in the heart or in the wall of blood vessels, react, among other things. on the different calcium concentration in each individual cell. If the calcium in the cells increases, the muscle cells become more willing to contract, i.e. they contract and perform muscle movement. In the heart, increased muscle movement leads to a stronger heartbeat and thus to rising blood pressure. On the outer wall of the blood vessel, increased muscle movement leads to a shrinking of the vessel lumen. The blood has to flow faster in order to get through a smaller diameter in the same time. Again, the effect is an increase in blood pressure. Calcium gets into the smooth muscle cells via docking points (so-called receptors). A distinction is made here between voltage-dependent calcium channels and receptor-dependent calcium channels. If you do not act on the mechanism, as is the case with all healthy people, the inward and outward flow of calcium is regulated by itself. The calcium mostly comes from the blood and from the tissue adjacent to cells. Nifedipine now inhibits this calcium influx by attaching itself to the channels and blocking them. The result is that the calcium influx is reduced and the muscle cells only receive a reduced amount of the calcium required for muscle movement. All muscle movements of the smooth muscle cells that are dependent on an increased calcium level can only be triggered to a reduced extent. In the heart, this means that calcium antagonists lower blood pressure (e.g. the substance verapamil). A blockage of the calcium channels in the vascular muscle cells prevents the muscles from contracting so much and thus the vascular diameter is not reduced or even expanded. The blood can flow more slowly, the blood pressure drops. While calcium antagonists of the nifedipine type act more on the vascular muscle cells, the substance group of the benzothiazepines and the phenylalkylamines are more effective on the heart and other organs that are controlled by smooth muscle cells
Calcium antagonists become to Blood pressure regulation in high blood pressure used. Especially Adalat® is used for high blood pressure and especially for so-called hypertensive crises (the blood pressure reaches values above 200 mmHg, but there is no organic impairment) and the so-called hypertensive emergency (Blood pressure values higher than 200 mmHg with organic damage). Patients under a coronary artery disease suffer frequently as well Calcium antagonists prescribed. As part of the coronary artery disease Adalat® is mainly used in the so-called stable angina pectoris used. Under this clinical picture one understands a Feeling of pressure on the chest under pressure. The symptoms can also be accompanied by shortness of breath. In contrast to unstable angina pectoris, in which the same symptoms occur even at rest, the stable angina pectoris still represents not an absolute emergency represent. a further application areat is also the rare one Raynaud's phenomenonin which it becomes a sudden narrowing of the arterial vessels of the fingers comes. Patients then usually complain of cold and white fingers. This condition usually improves after a few minutes and can e.g. by massage also be treated. In some cases, however, a calcium antagonist is used to reduce the spastic muscle contraction of the finger vessels by reducing the influx of calcium.
Adalat® as a labor inhibitor
In some cases Adalat® can be used as a contraceptive (medical: for tocolysis). However, it is not a first-choice product and is not officially approved for this purpose. In patients with comorbidities such as high blood pressure or diabetes (“diabetes”), various studies have shown advantages of the active ingredient in Adalat (nifedipine) over other drugs that are used to inhibit labor. Serious side effects, in particular, are less common than with other contraceptives. However, since Adalat is not approved for this so-called tocolysis, it can only be used as “off-label use” (contrary to the actually approved provision on the responsibility of the doctor).
Further interesting information on the topic can be found at: Premature labor
Adalat® is metabolized to 90% after ingestion. It then gets to the liver where a large proportion is already metabolized and is no longer available for the actual effect. The portion that still can work in the body, is around 45-65%.
Interaction with other drugs
Drugs that are also a Lowering blood pressure effect should only controlled with Adalat® combined because the blood pressure lowering effect of both substances is mutually reinforcing (In the case of high blood pressure that is difficult to control, this is even desirable).
Also the combination with certain to anesthesia substances used should be carried out with caution, as this also leads to an intensifying (here then unwanted) Lowering blood pressure would come. Nifedipine also affects the metabolism of other drugs. In the simultaneous administration from Adalat® and quinidine it must be noted that the Quinidine levels under Adalat combination initially sinks, at Discontinuation of the drug but shoots up in an uncontrolled manner. Also in the metabolism of substances Digoxin and Theophilline Adalat® intervenes, as all substances are broken down by the same enzyme in the liver. This means that when Adalat® is administered, the Increased drug level of the substances mentioned and thus has an unwanted increased effect (Digoxin is used in the Heart failure therapy used, theophilline at the Asthma therapy). The combination with the so-called NSAID (ASS, Ibuprofen, Paracetamol) that go to Fight pain, Lowering of fever and Anti-inflammatory are used, the effect that Adalat® is hindered in its effectiveness and cannot reduce blood pressure as strongly as it should. The reason is that NSAIDs are water and sodium hold back in the vasculature and such Increase in blood pressure have as a consequence.
Adalat® should not be used if the patient also has a Heart failure (Heart failure) is present or if a unstable angina pectoris is known. Also, it shouldn't be used in patients with severe abnormal heart changese.g. a Cardiomyopathy or one Rigidity of the heart valve (Aortic stenosis), are given. The reason is that Adalat® is not only used for Lowering blood pressurebut to Drop in blood pressure comes. With such a drop, the damaged heart muscle cells cannot be supplied with sufficient blood, which further exacerbates the disease of the heart.
Is with the patient a known to have low blood pressure, should also no Adalat® or comparable preparations are given, as this would further reduce the already low blood pressure. Adalat® and some other drugs in this group of substances can be taken in the 1st trimester of pregnancy, but are more of a second choice.
Find out more about alternative preparations in pregnancy: Medication in Pregnancy and Therapy of high blood pressure in pregnancy
Due to the increased vasodilation by Adalat® (Nifedipine) it can lead to an outflow of liquid into the tissue. Result from it Edemathat are reflected mainly on the legs. In this case you should use the Elevate your legs and possibly also wrap. A Dose reduction of the drug should also be carried out in this case. It must also be considered whether Adalat should not be completely discontinued and an alternative preparation should be used.
In case of a stable angina pectoris, one arterial hypertension or one Raynaud's Syndrome should 3 times 5-10 mg are given. If necessary, the drug can also be increased. The maximum dose amounts 60 mg a day. In retarded form (i.e. the active ingredient is released over a certain period of time) should 2x 20 mg and a Maximum dose of 80 mg per day administered. The therapy of a hypertensive emergency should come with a capsule of 10 mg to bite into be treated. With a Onset of action is after the earliest 30 minutes to be expected. Adalat® can also be given via an infusion into a vein. Here the gift should be converted from 5 mg in 4-8 hours respectively. A Maximum dose from 15-30 mg / day should not be exceeded.