What are muscle relaxants?
Muscle relaxants are special drugs that cause the muscle cells to relax. This effect is particularly used in anesthesia to induce anesthesia. Muscle relaxation is also of great importance for the ventilation of a patient during an operation.
In addition, muscle relaxants can be used to release tense muscles in the neck or back area. There are two groups of muscle relaxants – peripheral and central muscle relaxants. They differ in their place of action. Peripheral muscle relaxants act directly on the muscles, whereas central muscle relaxants act in the central nervous system, where they reduce muscle tone.
These muscle relaxers are available
Muscle relaxants are basically divided into two main groups. On the one hand, there are the peripheral muscle relaxants, which attack the muscle directly or the transmission between nerve and muscle. The central muscle relaxants, which act in the central nervous system, i.e. the brain and spinal cord, differ from these.
They are intended to reduce the basic tension of the muscles and thus relieve cramps. Tense muscles are often a symptom or cause of back pain, as almost everyone knows it. Here, central muscle relaxants are usually used.
Their effect is less strong and they tend to regulate the tension of the musculature. In contrast, peripheral muscle relaxants are mainly used in anaesthesia and surgery. These act directly on the musculature and, if dosed sufficiently, can cause complete flaccid but temporary paralysis.
Peripheral muscle relaxants in particular can be divided into further subgroups according to their exact mechanisms of action. Benzodiazepines, which are actually known as sleeping pills or sedatives, also act as muscle relaxants. The reason for this lies in their mechanism of action.
They act on so-called GABA receptors in the central nervous system. GABA is a so-called inhibitory neurotransmitter in the brain. Under the action of benzodiazepines, GABA’s effect is increased.
The result is drowsiness, anxiety release, but also muscle relaxation. The muscle-relaxing effect is intensified by a general release of anxiety or relaxation, as the muscles become involuntarily tense when anxious or excited. However, benzodiazepines are not free from side effects.
A major danger in taking benzodiazepines is their potential for dependence. Benzodiazepines can easily cause addiction and even withdrawal when discontinued. This is especially true if they are used continuously.
Addiction can exist after only weeks. Ortoton is the trade name of the active substance methocarbamol. This is also a centrally acting muscle relaxant.
Its mechanism of action is different from that of benzodiazepines. It acts directly in the spinal cord. There it probably inhibits reflex lines.
If these reflex lines are active, muscle tension increases. If they are inhibited by methocarbamol, it decreases. However, the exact mechanism of action is not yet fully understood.
The effectiveness of methocarbamol has not yet been conclusively proven. An advantage of methocarbamol is that it causes fatigue to a lesser extent than, for example, benzodiazepines. Because of its central mechanism of action, the strength of the muscles is not noticeably affected.
Nor does it appear to affect coordination. Adverse effects are rare. However, methocarbamol in higher doses may have a dampening effect and may even cause dependency.
The risk, however, is lower compared with benzodiazepines. At the same time, there are critical voices questioning the efficacy of methocarbamol in relieving tension. The active substance contained in Sirdalud is called tizanidine.
It also acts in the central nervous system. Here it attacks so-called α2 adrenoceptors. This also causes a reduction in muscle tension.
However, adrenoceptors not only control muscle tension, but also important bodily functions such as blood pressure. An important side effect of Tizanidin is therefore the so-called orthostatic dysregulation. The body is no longer effectively able to adapt blood pressure to changing conditions, such as the change from lying down to standing.
This manifests itself as a drop in blood pressure. In the worst case, this can lead to fainting.Other important adverse effects of Tizanidin are fatigue and dry mouth. Tizanidine may also have an analgesic effect.
However, this can be beneficial in cases of severe muscle tension. A great advantage of tizanidine is that its dependence potential is much lower than that of comparable drugs such as the benzodiazepines. However, sudden cessation of Tizanidine may cause palpitations or high blood pressure. This is particularly the case if Tizanidine has been taken over a long period of time or in high doses. Caution is therefore advised, especially in the case of known heart diseases.
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