MAO inhibitors
definition
MAO stands for monoamine oxidase and is an enzyme in the human body that breaks down some neurotransmitters in the brain. By splitting the neurotransmitters lose their effect. The MAOIs are drugs that are designed to prevent this split.
They are mainly used in the treatment of depression and Parkinson's disease. The MAO inhibitors are only available from a pharmacy and require a prescription.
effect
As previously described, MAOIs prevent some neurotransmitters from breaking down in the brain. These neurotransmitters are primarily Dopamine, serotonin and Norepinephrine, the so-called monoamines. These neurotransmitters are used to transmit signals in the brain.
Dopamine For example, plays a significant role for the Motor skills, For psychological processes and for the Hormonal balance.
The neurotransmitter Norepinephrine is both a hormone and a neurotransmitter and plays an important role in the sympathetic nervous system.
Also Serotonin is both a hormone and a neurotransmitter. In the central nervous system in particular, it influences a large number of functions.
If these neurotransmitters are split, they lose their signal transmission effect. Through the MAOIs will the The concentration of the substances kept artificially high.
There are two different types of enzymes, the so-called MAO A- and MAO B-Enzyme types.
The MAO-A enzyme types are more responsible for breaking down noradrenalis and serotonin, whereas the MAO-B types break down other monoamines.
Dopamine and tyramine are broken down by both the MAO-A and MAO-B forms.
If the MAOIs only block one of the two types of enzyme, they are called selective, otherwise they are called nonselective / unselective. In addition, the MAO inhibitors can have reversible properties. But there are also MAO inhibitors whose effects cannot be reversed. They are then called irreversible. Because of these different properties, the different types of monoamine oxidase inhibitors also have different areas of application.
indication
MAOIs prevent the split from a few Neurotransmitters in the brain. These neurotransmitters are primarily Dopamine, serotonin and Norepinephrine, the so-called Monoamines.
These neurotransmitters are used to transmit signals in the brain. Dopamine For example, it plays an important role in motor skills, psychological processes and the hormonal balance.
The neurotransmitter Norepinephrine is both a hormone and a neurotransmitter and plays an important role in the sympathetic nervous system.
Also Serotonin is both a hormone and a neurotransmitter. In the central nervous system in particular, it influences a large number of functions. If these neurotransmitters are split, they lose their signal transmission effect. The concentration of the substances is kept artificially high by the MAO inhibitors.
There are two different types of enzymes, the so-called MAO A- and MAO B-Enzyme types. The MAO-A enzyme types are more responsible for breaking down noradrenalis and serotonin, whereas the MAO-B types break down other monoamines. Dopamine and tyramine are broken down by both the MAO-A and MAO-B forms. If the MAOIs only block one of the two types of enzyme, they are called selective, otherwise they are called nonselective / unselective. In addition, the MAO inhibitors can have reversible properties. But there are also MAO inhibitors whose effects cannot be reversed. They are then called irreversible. Because of these different properties, the different types of monoamine oxidase inhibitors also have different areas of application.
Side effects of MAOIs
The side effects of MAOIs vary widely. In principle one can say that drugs that inhibit only one of the two MAO sub-forms, fewer side effects cause than those that inhibit both sub-forms at the same time.
Typical side effects that show up when taking the MAOIs are Restlessness and insomnia. Also the exact opposite, namely fatigue, can occur. In addition, the patient can have a Dry mouth to notice. dizziness and nausea can also be possible consequences of ingestion. Some MAOIs can also have side effects Hallucinations or Cardiac arrhythmias occur.
Also a so-called tremor can be a side effect of MAOIs. Here it comes to rhythmic twitching of muscle groups, especially the hands.
With non-selective MAOIs like that Tranylcypromine, the side effects and interactions with other drugs, when consuming at the same time red wine and cheese, increase significantly.
Cigarettes
Cigarettes are also linked to the MAOIs. Cigarettes contain a number of substances that addicted can do.
In relation to the inhibition of monoamine oxidase, the contained in the tobacco leaf and artificially added sugar a role. When smoking the cigarette, the burning of the sugar and other substances creates the dangerous substrate acetaldehyde. This substrate acts like a medicinal MAOIs.
Smoking thus leads to a reduced breakdown of the neurotransmitters serotonin, noradrenaline and dopamine and thus to a prolonged effect of these messenger substances. Because of this MAO-inhibiting effect, the Potential for addiction to smoking of cigarettes increased, because the neurotransmitters are present in increased concentrations in the brain and can therefore develop their effect better.
MAO inhibitors and venlafaxine
Venlafaxine is also a drug that is used to treat depression. It belongs to the group of so-called "selective serotonin noradrenaline reuptake inhibitors" (SSNRI). Since, as the name suggests, it hinders the absorption of serotonin, special care should be taken when combining it with MAOIs.
Venlafaxine and MAOIs should not be taken together. The so-called serotonin syndrome can develop in the patient when taking venlafaxine. If this occurs, the patient is in potential mortal danger. The syndrome develops when there is an accumulation of serotonin in the body. This often happens when multiple drugs are taken that affect the serotonin system. Serotonin syndrome manifests itself as an increase in heart rate, increased sweating, headaches and diarrhea. Restlessness and disorders of consciousness can also be symptoms of serotonin syndrome.
If these symptoms occur while taking venlafaxine, a doctor should be consulted as soon as possible and the drug should be discontinued immediately.
Further information is available from: Serotonin Syndrome
