AMIODARONE

introduction

Amiodarone can be used, for example, if the conduction of excitation to the heart is impaired.

The active ingredient amiodarone is used in the treatment of cardiac arrhythmias; the drug is one of the class III antiarrhythmics.
If the conduction of excitation to the heart is disturbed, the heart rate is too fast and irregular (Tachycardia and Tachyarrhythmia) and additional beats independent of the normal heart rhythm (extrasystole), amiodarone can be used to help.
In addition to its good effectiveness on the heart, the drug has numerous side effects that should not be despised.

Application of amiodarone

Amiodarone is a prescription drug and as tablet available in 200 mg and 100 mg dosage.
In tablets, the active ingredient is usually given as amiodarone hydrochloride. After starting treatment it takes a few days for the full effect to take effect.
Through a slowed degradation of the drug amiodarone in the body it takes after amiodarone is discontinued about a month until the effect is completely canceled is.

The attending physician decides on the duration of the therapy. For the treatment of acute cardiac arrhythmias, amiodarone is given as an emergency injection directly into the vein.

Use of amiodarone

The respective dose is determined by the attending physician.
Usually a Satiety dose administered until one in the tissue sufficient mirrorl of amiodarone is present.
After that will reduced to a maintenance dose.
The loading dose is 600 mg of amiodarone over 8 to 10 days. Accordingly, the patient receives either 3 times 2 tablets with 200 mg active ingredient each or 6 times 1 tablet with 100 mg active ingredient each spread over the day. It is rarely necessary to increase to 1200 mg amiodarone per day, but this is only determined by the attending physician.
The subsequent maintenance dose is 200 mg amiodarone 5 times a week. Accordingly, the patient receives either 1 tablet with 200 mg of active ingredient each 5 days a week or 2 tablets with 100 mg of active ingredient each 5 times a week. Here, too, it is seldom necessary to increase to 200-600 mg amiodarone per day. Here, too, the setting is made by the attending physician.
The tablets should whole during or after a meal be taken, it is on adequate hydration to pay attention.

Contraindications

Amiodarone should not be used Allergy to the active ingredient or any of the other ingredients of the drug, if you have an allergy to iodine, if you have slowed heartbeat <55 / min (Sinus bradycardia), with an existing QT prolongation in the ECG or conduction delays in the heart (to be determined by the doctor) Potassium deficiency (Hypokalemia), Thyroid disease, at the same time Therapy with MAO inhibitors (used to treat depressed patients) or drugs that can trigger life-threatening cardiac arrhythmias (so-called Torsade de Pointes), as well as with simultaneous use of Cholesterol lowering agent Simvastatin in a daily dose greater than 20 mg per day.

Mode of action (for very interested readers)

In order for large amounts of blood to circulate uninterruptedly in the body's circulation, the heart needs regular pumping.
Heart muscle cells are excited for this at regular intervals. The heart has its own conduction system; in a healthy heart, the heart muscle cells are excited via the so-called sinus node with a natural frequency of approx. 70 / min.
Action potentials develop on the heart muscle cells as a result of the influx of certain ions into the interior of the cell.
The heart muscle cell depolarizes and the voltage inside and outside of the cell is reversed from -70 mV to +30 mV.
The trigger for this is an increased positive sodium influx into the cell interior. After a plateau phase at 0 mV, the excitation recedes and the cell repolarizes.
A positive potassium outflow and a negative chloride inflow are responsible for this; they ensure that the heart muscle cells are brought back to a resting potential of -70 mV. Now one action potential has ended and another can arise.
Amiodarone acts as a potassium channel blocker on the repolarization phase of the action potential. The potassium outflow is reduced and thereby the so-called refractory period is extended, in which the cell cannot react to a new stimulus because it is still repolarizing. This effect can prevent circling excitations such as atrial fibrillation and the formation of extrasystoles, while the contraction force of the heart is fully retained.
In addition, amiodarone causes the heart rate to decrease and the coronary arteries to expand, which means that the heart can be better supplied with oxygen.