Serotonin Reuptake Antagonists and Inhibitors (AIRSs)

Among all mental problems, depression is, along with the set of disorders linked to anxiety, one of the most common in the world. The treatment of this type of problem has been something that has generated extensive research from multiple scientific disciplines, one of them being psychopharmacology.

From this discipline, different therapeutic alternatives have been generated and synthesized, existing in currently a large number of substances that contribute to alleviating both depression and other issues. One of the types of synthesized drugs is extremely interesting since it works in an apparently contrary way to that of other drugs. Is about Serotonin Reuptake Antagonists and Inhibitors or AIRSs.

• Related article: "Types of antidepressants: characteristics and effects"

Serotonin Reuptake Antagonists and Inhibitors: what are they?

Serotonin Antagonists and Reuptake Inhibitors or AIRSs (Serotonin Antagonist and Reuptake Inhibitor or SARIs in English) are a type of atypical antidepressant and relatively novel ones characterized by having an unusual mechanism of action and apparently contrary to the way other antidepressants work.

On the one hand, they inhibit the reuptake of serotonin, which increases its levels in the brain, but on the other hand, they exert effects contrary to it in certain receptors of the same, which in principle reduces the presence and action of this neurotransmitter.

The main and best-known representative of this type of drug is trazodone., a drug with therapeutic success both in depression and in other conditions with anxious characteristics. Other substances such as nefazodone also have characteristics and mechanisms of action of this type of drug, although since it also acts to a large extent on other neurotransmitters, sometimes they do not fall into this category. classification.

However, despite its atypical functioning, this group of drugs have been shown to be useful for the treatment of depressive symptoms as well as for other mental conditions and problems.

• You may be interested: "Types of psychotropic drugs: uses and side effects"

Mechanism of action

As we have mentioned previously, antagonists and serotonin reuptake inhibitors have a different mechanism of action compared to other similar drugs.

The AIRSs They have a dual mechanism of action, generating mainly two types of changes in brain chemistry.

On the one hand, they are characterized by generating a block in the reuptake of serotonin in presynaptic neurons, which makes this neurotransmitter more present in the synaptic space and can be used by postsynaptic neurons.

On the other hand, the action of this type of drug has an antagonistic effect on 5HT2A and 5HT2C receptors, preventing serotonin from acting on them. Of course, at 5HT1A receptors the effect is agonist, facilitating effects similar to those of serotonin.

It is this last mechanism of action that makes the way AIRS act something different and peculiar. if we compare it with other types of better-known antidepressants, it has anxiolytic and hypnotic properties.

Therapeutic indications of AIRSs

Serotonin antagonists and reuptake inhibitors are substances classified as antidepressants, meaning Its main indication is the treatment of major depression.

Likewise, these drugs have anxiolytic action, making them also effective for the treatment of various conditions linked to anxiety. Thus, they have been used (specifically with regard to trazodone) in problems such as anxiety generalized, erectile dysfunction of psychogenic origin, bulimia nervosa, OCD, or depression syndromes. abstinence.

They are also used in sleep problems, such as insomnia, because They have hypnotic and sedative effect. This effect has also been taken advantage of in some cases of Bipolar disorder or in psychotic disorders such as schizophrenia.

• You may be interested: "Major depression: symptoms, causes and treatment"

Side effects

Like all psychotropic drugs, AIRSs can have various side effects. Nausea and vomiting are common (especially in the first weeks), sedation and fatigue, tiredness, low blood pressure, edema or blurred vision.

There may also be a risk that suicidal ideation may appear more easily in the first weeks, something common to many antidepressants. Priapism and arrhythmias can also appear and have consequences in people with previous cardiovascular problems.

It should be taken into account that the main representative of these drugs is excreted with breast milk, which is why it is contraindicated in pregnant and lactating women. Also in people with heart problems and previous heart attacks and liver or kidney problems. Special caution should be taken in cases of bipolarity or psychotic disorder, since it can favor a turn to manic symptoms or the appearance of positive symptoms such as hallucinations and agitation.