Barbiturates: Effects, Mechanisms Of Action And Toxicity
Anxiety and the different problems it can cause in our lives are widely known today. But although it is considered that our current pace of life makes it easier for these types of problems to appear, the truth is that anxiety has been known since ancient times.
Throughout history, attempts have been made to create different effective techniques and substances against anxiety. One of the most successful types of psychotropic drugs until the arrival of benzodiazepines. it has been the barbiturates
Barbiturates are a type of psycholeptic psychotropic drug, that is, it has calming and depressant effects on the central nervous system. These medications are derivatives of barbituric acid, which was first synthesized by Adolf von Baeyer in 1863. However, the first medications properly known as barbiturates did not emerge until 1903, by Emil Fischer and Josef von Mering. They are considered the first psychotropic drugs with hypnotic-sedative effects.
The action of barbiturates on the nervous system causes a high level of sedation, relaxing and reducing muscular and mental activity. They have a great effect as a hypnotic, anesthetic and analgesic In addition, they are useful in the treatment of seizures and other motor symptoms.
On the other hand, barbiturates generate alterations in mood, like mild feelings of euphoria. Due to their effectiveness in reducing anxious symptoms, they were for a time the treatment of choice for symptoms of anxiety, depression and insomnia.
Risks of consumption
Barbiturates, although highly effective in the treatment of certain symptoms and problems, are highly toxic and have a high level of danger.
Despite their effectiveness, the use of barbiturates It poses a high risk to health, generating dependency very easily Furthermore, the doses that are therapeutic and those that are toxic are very close, which can cause poisoning and even overdose.
An overdose of barbiturates can lead to death in 1 in 4 cases. In fact, There are many deaths linked to overdose of these medications such as that of Marilyn Monroe.
Currently, barbiturates have been superseded by benzodiazepines, which have a higher level of safety, while at the same time they do not generate so much dependency or cause such serious side effects. Despite this, barbiturates continue to be used medically in specific cases in which other substances are not effective, such as anesthesia in surgical interventions or in neuropsychological examinations (always with a high level of control).
The risks are multiplied if barbiturates are mixed with other substances. In combination with depressant substances it can cause respiratory failure. Its combination with alcohol, antihistamines and depressant drugs They enhance the depressant effects, and the result can be fatal. On the other hand, taking activating substances in the quest to counteract the effects of barbiturates can in turn generate heart problems.
Another very important risk It has to do with the cases of pregnant women and nursing mothers Barbiturates, highly fat-soluble, can be transmitted through the placenta and breast milk. Likewise, an overdose can be dangerous for the life of the fetus, and an abortion may occur.
Some side effects
The consumption of these substances can cause a series of highly relevant side effects, which can even lead to death. Some of these effects may be the following.
1. Excessive sedation
Barbiturates have come to be used as anesthetics due to their powerful sedative effect. Although this can sometimes be sought, it can be detrimental to proper functioning and personal performance by causing excessive sleepiness that reduces the individual’s physical and mental capabilities. They can cause mild paralysis and tingling in different parts of the body.
2. Lack of coordination of different functions
The consumption of barbiturates can cause physical coordination problems, being more difficult to walk or even talk You should not drive under the influence of this type of medication even if you do not feel drowsy.
3. Cardiorespiratory problems
Barbiturates are highly potent psychotropic drugs as depressants of the nervous system, as we have just mentioned. However, this depression can lead to respiratory problems, and even in extreme cases there is a risk of going into cardiorespiratory arrest
Although barbiturates generally generate depressant effects on the nervous system that sedate the subject, in some people they can produce a high level of behavioral disinhibition, which can lead to actions that would not be carried out under normal circumstances. In fact, they have been used as supposed “truth serums.”
5. Risk of dependency
The addictive potential of this type of substance is very high, generating dependency with great ease. It is also easy to abuse its consumption, which is especially dangerous with this medication. The main reason is the high level of tolerance that it tends to cause, which means that an increasingly greater amount is needed to achieve the same effects as in the first doses.
6. Withdrawal syndrome
When a person dependent on barbiturates suddenly stops using them, they may suffer withdrawal syndrome. In the case of barbiturate withdrawal, it is common for the opposite effects to those of consumption of the substance to occur.
Specifically, it is easy to find restlessness, anxiety, aggression, gastrointestinal symptoms, insomnia or seizures. Hallucinations and delusions may also occur. It can cause a drop in voltage that is dangerous for survival. In fact, in some cases the withdrawal syndrome can be fatal. This is why both taking and stopping the consumption of these drugs must be scheduled with special caution, withdrawing gradually.
Mechanism of action
The operation of barbiturates is based mainly on facilitating the action of gamma-aminobutyric acid or GABA, which reduces the overload of the nervous system by making it difficult for nerve impulses to be produced and transmitted.
This promotion of GABA is carried out through the action of the drug on the ion channels sensitive to this hormone in the brain. Specifically hinder the entry of sodium into the neuron while facilitating the entry of chlorine into the cell.
Types of barbiturates
Barbiturates, like other medications, can be classified into several groups based on how long they take to take effect and how long the effects last. However, even when the effects end, their characteristics mean that they can remain in the body for a long time. We can identify 4 types of barbiturates
1. Ultra short action
Ultrashort-acting barbiturates They are characterized by having a half-life of several minutes long, its effects starting seconds after consumption. Within this group we can find thiopental and methohexital.
Those barbiturates such as hexobarbital, pentobarbital or secabarbital are known as short-acting, which begin their effects between ten and fifteen minutes after consumption. to last for about 3 or 4 hours
3. Intermediate action
Intermediate-acting barbiturates They usually take about an hour to take effect, lasting between 6 and 8 hours Within this type of barbiturates we find one of the best known and used in various procedures such as the Wada test, amobarbital.
4. Long action
Primidone and phenobarbital are some of the examples of long-acting barbiturates, which usually take more than an hour to take effect, but nevertheless tend to last around 12 hours.
Uses and applications
Although they have currently been replaced by other substances in the treatment of most conditions, barbiturates continue to be used in certain cases. Below are some of the uses that these substances currently have or have had in the past.
Neuropsychological examination
Barbiturates are used in some neuropsychological evaluation procedures. An example of this is the Wada test in which sodium amobarbital is used to sedate a specific area of ​​the brain and determine the functionality of areas linked to aspects such as laterality, memory or language.
Anesthetic
Some barbiturates are used both to initiate and maintain patients anesthetized during different surgical interventions. It is one of the main current applications.
Seizures
One of the indications for certain types of barbiturates is its use in cases where seizures appear since they contribute to controlling motor symptoms thanks to their sedative effect and the reinforcement of GABA, which helps inhibit the discharge of nervous impulses.
Brain trauma and accidents
barbiturates They are used to control and reduce the effects of cerebral infarctions as well as edema produced by different craniocerebral traumas.
Insomnia
Although other types of sedatives are currently used such as benzodiazepines, barbiturates They have been used in the past as sleeping pills
Anxiety
As with insomnia, other types of substances (the most common being benzodiazepines and some antidepressants) are currently used to treat anxiety, but in the past barbiturates were the main substance used as a treatment for anxiety
