Active substance
Nitrendipine
Introduction
Nitrendipine belongs to the group of calcium channel blockers or calcium antagonists. It is used for the treatment of high blood pressure (arterial hypertension) and as an acute medication in cases of blood pressure derailment (hypertensive emergency) (Bayotensin akut®). Within the group of calcium antagonists, nitrendipine belongs to the dihydropyridines. In contrast to other representatives of the calcium channel blockers (e.g. verapamil, diltiazem), it only attacks the blood vessels and hardly the heart, which is important for the indication and the spectrum of side effects.
Side effects
Typical side effects of Bayotensin® are those caused by its vasodilating effect. These include redness and overheating of the skin of the face and upper body (flushing), headaches, dizziness, fatigue, tingling in the arms and legs (paresthesia) and water retention in the legs (edema of the lower legs). A tremor of the hands (tremor) has also been reported.
Angina pectoris attacks (attacks of chest pain caused by temporary circulatory disturbances of the heart) can also occur or – in the case of pre-existing angina pectoris – these symptoms can become more severe. A faster beating of the heart (tachycardia) and heart stumbling (palpitations) can also occur. A very rare side effect is the development of a heart attack caused by nitrendipine.
Especially at the beginning of the treatment an increase in urine excretion can occur (polyuria). Nausea and flatulence can also occur. Due to the mechanism of action, an excessive lowering of blood pressure (hypotension) can occur.
Interactions
Various drugs can reduce the effect of nitrendipine because they activate a specific enzyme (CYP34A) that is responsible for the breakdown of nitrendipine. This means that nitrendipine is broken down more quickly. These drugs are called CYP inducers.
These include, among others: Other drugs inhibit the enzyme (CYP34A) and thus cause nitrendipine to be broken down less quickly. They are known as CYP inhibitors. These include drugs used to treat HIV (protease inhibitors), antiepileptic drugs (valproic acid), macrolide-type antibiotics, some drugs used to treat fungal diseases (antifungals) and grapefruit juice.
Grapefruit juice can be effective for up to three days after taking it, so grapefruit juice should be avoided during treatment. Simultaneous use of nitrendipine and beta-blockers should be handled with care and only under regular control. Intravenous administration of beta-blockers with simultaneous ingestion of nitrendipine should be avoided. – Rifampicin (antibiotic, mainly used to treat tuberculosis)
- Antiepileptic drugs
- Phenytoin
- Carbamazepine
- Barbiturates
- Phenobarbital.
Dosage
Nitrendipin/Bayotensin® is available in tablet form and as a solution (vials). The solution is used for the treatment of hypertensive emergency (blood pressure derailment), the tablet for the treatment of high blood pressure. The usual daily tablet dose for high blood pressure is 20 mg Bayotensin®.
Either one tablet of 10 mg each in the morning and evening or one tablet of 20 mg each per day. The daily dose can be increased to up to 40 mg if necessary. In the event of a blood pressure derailment, one vial (1 ml solution with 5 mg nitrendipine) can be taken if necessary, and after 30-60 minutes a second vial can be used if necessary.