The culture and society in which we live is characterized by a high level of dynamism and constant change, along with a high demand for the people who are part of it.

We are constantly required to be productive, proactive and foresighted , having to adapt both to the changes in today’s society and to the possible situations that might occur in the future. For this reason, we often worry about what might come, a concern that can lead us to aversive emotional states in the face of fear and tension about what might happen.

In this way, we can observe how stress and anxiety related disorders are increasingly prevalent, with anxiety problems being the most prevalent in the general population and in the clinic. In order to treat this type of problems, different types of treatments have been developed and synthesized, and among them, at a pharmacological level, several types of anxiolytics have been synthesized .

Analyzing the problem to be treated: anxiety

The different types of anxiolytics that will be discussed in this article have several points in common, but the main one is the type of problem they treat: anxiety.

While most people know what it is and have in fact experienced anxiety throughout their lives, it is a phenomenon that has often been difficult to define. Anxiety is considered to be that state of emotional discomfort that arises without any immediate stimulus or danger that generates it , being the anticipation of a future phenomenon that causes this reaction. Subjects suffering from anxiety have a high level of activation together with a high level of negative affectivity.

Although its origin is usually cognitive, the effects it produces can also be translated at a physiological level, producing reactions such as tachycardia, physical tension or sweating. It also causes effects at the behavioural level, such as the avoidance of situations that could lead to what causes anxiety. For example, fearing the recurrence of a phenomenon that occurred in the past can cause us to avoid similar situations in order to ensure that this is not possible.

Thus, taking into account the discomfort it causes and the fact that it can even invalidate important aspects of our lives (as for example in cases of individuals with agoraphobia), seeking a treatment that alleviates these problems has led to the creation of various treatments, such as anxiolytics in the case of pharmacological treatments .

Main types of anxiolytics

The general function of anxiolytics is to induce a decrease in activity, through a depressive action on the nervous system. To this end, most types of anxiolytic act on the gamma-aminobutyric acid or GABA and its receptors, enhancing the inhibitory action of this neurotransmitter.

Despite this, in recent times there has been an increase in the use of drugs with action on serotonin , leading to the use of antidepressants such as SSRIs as the drug of choice in some anxiety disorders. Below are some types of anxiolytic drugs.

1. Barbiturates

Prior to the arrival of benzodiazepines, these barbiturate acid derivatives were the most widely used type of anxiolytic at the time, having a high sedative potential despite the high risk of addiction and fatal overdose they entail. Its mechanism of action is based on preventing the flow of sodium to the neurons .

They were discovered by Emil Fischer in 1903, and their use continued until the 1970s or so, when the search for less dangerous, effective substances for anxiety led to the discovery of benzodiazepines. Despite this, some barbiturates such as amobarbital were and are used in a very controlled way in medical surgical interventions, as in the Wada test.

2. Meprobamate

This substance, like barbiturates, enjoyed a great reputation and prestige during a period of time due to its action on anxiety. Besides acting on anxiety processes it was used in cases of spasms, insomnia, alcoholic abstinence and migraines. It is a drug that acts in different regions of the nervous system, and can also have an effect on the spinal cord.

However, was no longer marketed because it was considered that the benefits it could bring did not outweigh the risks , causing confusion and loss of consciousness among other problems in addition to being highly addictive.

3. Benzodiazepines

This class of anxiolytic is the best known and most used at present , acting as indirect agonists of GABA in type A receptors. They increase the affinity of GABA for its receptor throughout the brain, but especially on the limbic system. They increase the affinity of GABA for its receptor throughout the brain, but especially on the limbic system.

They produce a relief of cognitive tension and depending on the dose a certain level of sedation, serving also as an anticonvulsant. Within this type of anxiolytics, some of the best known and most consumed are lorazepam, bromazepam (Lexatin), alprazolam, diacepam (Valium) and chlorazepate.

There are various types of benzodiazepines, depending on whether their life span in the body is short, medium or long, each having different advantages and disadvantages.

A short-lived benzodiazepine is one that lasts for a few hours, less than twelve. They have a very rapid effect and are very useful in cases where it is necessary to reduce anxiety quickly , such as in the case of anxiety crises or insomnia. On the other hand, they are more likely to cause addiction as they require more habitual consumption to maintain the effect of the drug, and are more frequent to have side effects.

Long-lived benzodiazepines are those that last more than 24 hours in the body. They have the disadvantage that, when prolonged, their action can have an additive effect with the previous dose, generally producing more sedation, but on the other hand, fewer doses are needed to keep the anxious symptoms under control, which makes addiction difficult.

Intermediate-acting benzodiazepines have a shelf life of about 12-24 hours, and are useful in cases where symptoms are to be treated more quickly than with a long-acting substance and without the substance remaining in the body so long, but without the need for constant intake of the drug to maintain the effect.

4. Buspirone

Buspirone is one of the few psychoactive drugs used in anxiety that acts on a neurotransmitter other than GABA . For this same reason, it has the advantage that unlike other types of anxiolytic drugs, it does not produce the same side effects, as there are no interactions with depressant substances or addiction, nor does it cause sedation.

This substance acts on serotonin, specifically as a partial agonist. However, it takes weeks to take effect, so it is not useful for anxiety attacks.

5. Antihistamines

This type of substance has been used on some occasions in cases of anxiety due to the sedation they produce, but apart from this effect they do not present any therapeutic advantage against anxiety.

6. Beta-adrenergic blockers

Beta-adrenergic blockers have occasionally been used as an adjuvant treatment because they seem to contribute to decrease somatic symptoms

Main risks and adverse effects

The administration of anxiolytics is something very common nowadays, but it has to be taken into account that as with all drugs, their consumption can imply a series of undesired side effects and even some serious risks. It is these risks and side effects of these drugs that have led to research into new formulations, moving from barbiturates to benzodiazepines and from these (although they are still among the most widely used today) to other substances.

Although the adverse effects will depend on the substance and active ingredient of the drug in question , in general it can be considered that the possible side effects of the different types of anxiolytics include the following .

Addiction and dependence

The different types of anxiolytics have proven to be highly addictive among their users . For this reason, their consumption should be very much regulated, and it is generally recommended that the administration of this type of drug be carried out during not very long periods of time (around two to four weeks).

Similarly, abrupt withdrawal can cause withdrawal syndromes and rebound effects, so that at the time of stopping consumption, the cessation should be gradual.

Risk of intoxication and overdose

Overconsumption of some types of anti-anxiety drugs can cause an overdose . These overdoses can be really dangerous and can cause the death of the individual. In the case of barbiturates the risk of overdose and death is very high, this being one of the main causes of the development of other substances such as benzodiazepines.

For benzodiazepines, there is also some risk of death, but unless combined with other substances which enhance depression of the nervous system (including alcohol), or unless the body is weakened as in the case of the elderly, death from this cause is rare.

Sedation and activity reduction

The fact that they produce a depression of the nervous system means that most anxiolytics (with exceptions such as buspirone), can cause drowsiness , and therefore decrease the level of functionality and performance in some vital areas by reducing concentration and speed of reaction.

Paradoxical reaction

In rare cases, anxiolytics can have the opposite effect to that expected , causing hyperactivation and irritability. In these cases it is necessary to see a doctor immediately.

Bibliographic references:

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