Types of antidepressants: characteristics and effects.

The psychotropic drugs that combat depression are these.

Mood disorders are, after anxiety disorders, the most prevalent in the population. Within these types of disorder, depression is the best known and most frequent.

It is a disorder that causes major problems in virtually all areas of human life, affecting both cognitive and emotional and interpersonal. For this reason, its treatment is one of the main objectives of psychology and psychiatry, with different types of treatments being developed both at the psychological level, such as cognitive-behavioral treatment, and pharmacological treatment in the form of antidepressants.

Regarding the latter, research over the course of history has produced numerous types of antidepressants. in order to produce an improvement in the depressive symptomatology avoiding side effects as much as possible.

It is precisely about the latter that we will discuss in the following article: what are the different varieties of antidepressants, what characterizes them and what are their side effects.

Recalling concepts: what is depression?

The main objective of the different types of antidepressants is to treat depression.. Based on this premise, it is justified to make a brief review of what we consider depression. On a clinical level, depression is considered to be that condition in which there is a sad mood (which can be seen as irritable in the case of childhood depression) together with the absence of motivation and of the experience of pleasure, together with other symptoms such as sleep or weight problems.

Depressed people tend to have a high level of passivity at a vital level, feeling that they have little control over their lives and frequently experiencing feelings of hopelessness. Those suffering from depression therefore present a high level of negative affect, together with a low level of positive affect and, in general, they tend to present a low level of activation both mentally and physiologically.

Thus, the different types of professionals who are in charge of working to improve the situation of these people have to find methods and mechanisms that allow them to face these difficulties. different types of antidepressants described below.

Main types of antidepressants

The different antidepressants have different mechanisms of action, but the main hypotheses and treatments explain depression from the degradation of monoamines and/or serotonin, so the antidepressants created are mainly focused on preventing the degradation of these substances and keeping them longer in the synaptic space.

1. MonoAmino Oxidase enzyme inhibitors or MAOIs

These are the first antidepressants to be discovered. Their action is based, as in the other types of antidepressants, on preventing the degradation of monoamines by concentrating on a particular enzyme.. This enzyme is monoamine oxidase, which is released from the presynaptic neuron when it captures an excess of monoamines in the brain synapse in order to eliminate this excess. Thus, eliminating or blocking this enzyme prevents the degradation of monoamines in the synaptic space, resulting in a greater availability of these neurotransmitters.

However, this type of Antidepressant However, this type of antidepressant presents a high risk to healthHowever, this type of antidepressant presents a high health risk, since in interaction with substances containing thiamine (a substance easily found in a wide variety of foods) it can provoke hypertensive crises, together with other unpleasant side effects. For this reason they are mainly used in cases where other antidepressants have not shown any effect.

Types of MAOIs

There are two subtypes of MAOIs. The first subtype is that of the irreversible monoamine oxidase inhibitorswhose main mechanism of action is the complete destruction of this enzyme, so that until it is not generated again, its basic functionality is lost. This type of antidepressant is the one that presents the highest risk, being dangerous its interaction with other substances rich in thiamine and having to carefully monitor the food to be consumed to avoid serious health problems.

A second subgroup are the reversible monoamine oxidase inhibitors or RIMA, which are preferable to other types of MAOIs because they do not pose such a high risk and do not tend to interact with the diet. They work by temporarily inhibiting the function of the enzyme. Moclobemide is one of the substances that form part of this type of antidepressant.

2. Tricyclic and tetracyclic antidepressants

These drugs are, after MAOIs, the oldest and for a long period of time the most widely used antidepressants. Their mechanism of action is based on preventing the reuptake of serotonin and norepinephrine. However, its action is non-specific, affecting other hormones such as acetylcholine, histamine and dopamine. As a result, they can have serious side effects and can even be addictive.

An overdose of this type of substance is potentially fatal.. For these reasons and with the discovery of new substances, they are no longer used, but can still be found in clinical practice due to their greater effect in cases of severe depression.

3. Selective Serotonin Reuptake Inhibitors or SSRIs

Selective serotonin reuptake inhibitors are currently the most widely used type of antidepressant in clinical practice, being the treatment of choice in cases of depression, among other things because the side effects they produce are not as intense as those of other drugs used for the same purpose.

These are psychotropic drugs that act by specifically inhibiting the reabsorption of serotonin, with no effect on other neurotransmitters.and have no effect on other neurotransmitters. Although they may produce some side effects, these are usually mild (nausea, vomiting or light sedation among others), they are one of the safest classes, being applied in patients who have not had previous contact with antidepressants.

In addition, the relationship between depression and anxiety and the specific mechanism of action of the SSRI has also led to its use as the treatment of choice in some anxiety disorders.

4. Selective Serotonin and Norepinephrine Reuptake Inhibitors or SNRIs

This type of antidepressant, the best known exponents of which are venlafaxine and duloxetine, act on serotonin and norepinephrine in the same way as tricyclics.. The main difference with this other type of antidepressant lies in their specificity, i.e. while dual inhibitors of serotonin and noradrenaline have an effect only on these two neurotransmitters, tricyclics have an effect on other substances such as acetylcholine and can produce side effects.

Since they work not only on serotonin but also on noradrenaline, these drugs manifest a relatively faster effect than other substances.

5. Selective Dopamine-Norepinephrine Reuptake Inhibitor: Bupropion

Although this substance is best known for its usefulness in the detoxification of nicotine and other substances, bupropion has been shown to have positive effects in cases of depressionby inhibiting the transport of dopamine and noradrenaline.

Risks and side effects

As with all psychotropic drugs, the use of different types of antidepressants may entail various risks and side effects. It should be borne in mind that between the first administration of the antidepressant and its therapeutic action, in general, between two and four weeks may elapse because the neurons have to undergo a process of adaptation and modification of their receptors, especially with regard to serotonin.

However, the presence of side effects may occur before the therapeutic effects are noticed.For this reason, treatment with antidepressants is often discontinued and abandoned on many occasions. Some of the symptoms and risks of the consumption of the different types of antidepressants available are the following.

Dependence

Some types of antidepressants can generate tolerance and dependence.Tricyclics are an example of this. Likewise, the abrupt cessation of its consumption can generate withdrawal syndromes and rebound effects, making it necessary to schedule both its consumption and its cessation. That is why sometimes it is not recommended to make an abrupt withdrawal of its consumption, but a more gradual one that allows the body to adapt to the new situation.

Overdose

Taking an excessive amount of antidepressants can lead to intoxication and overdose.The latter can be lethal. Tricyclics are some of the drugs that have registered cases of this phenomenon, a fact to be taken into account when medicating patients with suicidal ideations.

Hypertensive crisis

This type of side effect is one of the greatest risks produced by MAOIs. It is due to the interaction of this substance with substances rich in proteins and thiamine, frequent elements in food. For this reason strict control of diet and blood tests are necessary to prevent problems..

Sexual and genital symptoms

The taking of some antidepressants sometimes produces a decrease in the libido of those who take them, desire or may cause situations such as anorgasmia or delayed ejaculation. or delayed ejaculation. This occurs because the hormonal imbalance produced by the consumption of these substances is very noticeable in sexual behavior, as this is very sensitive to this type of changes.

Drowsiness and sleep problems

Many types of antidepressants cause drowsiness and sedation as a secondary symptom. Others, such as MAOIs, can even suppress REM or paradoxical sleep, also causing sleep problems.They can also cause problems in consolidating new knowledge.

Manic symptoms

Some substances cause a change from a depressed to a manic state. An example of this is bupropion.

Other somatic and gastrointestinal symptoms

Nausea and vomiting are common with the intake of these substances.. as well as headaches and tremors. In fact, these types of symptoms are the most common secondary symptoms during the consumption of antidepressants, being generally mild. Many of these alterations appear initially and with the appearance of tolerance to the substance they disappear.

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