Psychoactive drugs
As we all know, the use of substances with properties that contribute to improving the symptoms of an illness or disorder is a key element in medicine, being used to return the body to its state of natural balance. In this article we will provide you the types of psychoactive drugs.
In the case of psychological disorders, the presence of many different problems has led to the investigation of various treatment options, including pharmacological ones.
Types of psychotropic and usages
The fact that there are many different symptoms and disorders has caused a wide variety of drugs to treat them, divided into different types of psychotropic drugs. None of these categories is, by itself, better than the others, and their usefulness will depend on each case. However, clinical psychologists and psychiatrists must know them all in order to offer the best possible treatment to their patients .
Let’s continue to see below the different types of psychotropic drugs that exist in reality.
1. Neuroleptics / antipsychotics
Mainly used as a method of controlling psychotic crises , this group of psychotropic drugs was called major tranquilizers due to the level of sedation caused by early versions. There are different groups within this conglomerate, mainly affecting dopamine transmission in distant brain regions.
Within the neuroleptics, we can find:
1.1 Classic / typical antipsychotics
The mechanism of action of these substances is based on the blockade of dopamine receptors (specifically D2 receptors) of the mesolimbic pathway, a blockade that causes the cessation of the positive symptoms of schizophrenia and psychotic disorders (hallucinations, delusions, etc.).
However, the performance of this type of medication does not only occur in the mesolimbic circuit, but also affects the rest of the dopaminergic pathways and can cause side effects in different facets such as movement (for example, tremors, tardive dyskinesias, restlessness or low spontaneity). ) or reproduction (emission of milk by the breasts, regardless of gender or amenorrhea, among others).
In addition, these drugs have very little effect on negative symptoms (lack of logic, inappropriate language, motor and mental slowness), being practically non-existent in this regard. Within this group, you can find chlorpromazine, haloperidol or pimozide, among others.
1.2 Atypical antipsychotics
In order to produce an improvement also in the negative type symptoms and to reduce the side effects due to the involvement of other pathways, atypical antipsychotics were synthesized. This type of neuroleptic works by blocking dopamine and serotonin , blocking the second, eliminating the side effects of blocking the first.
Furthermore, given the greater number of serotonin receptors in the cortex and the fact that it acts as a dopamine inhibitor, dopamine inhibition causes an increase in dopamine performance in mesocortical areas, which causes improvement in negative symptoms. However, they can have some side effects such as hypotension, tachycardia, dizziness or sedation. With clozapine, there is also a risk of agranulocytosis, a change in the red and white blood cell count that can be fatal if left unchecked.
Within this group, we find clozapine, risperidone, olanzapine, quetiapine, sulpiride and ziprasidone. Because they belong to different families, they can have a greater or lesser effect on certain alterations, working not only for psychotic disorders, but for others, such as disorders due to tics, autism, OCD and mood disorders.
2. Anxiolytics and hypnotic sedatives
The presence of anxiety problems is a frequent phenomenon in today’s society , being the most frequent type of disorder. To combat it, anxiolytics were generated.
This type of psychoactive drug acts by exerting a depressing effect on the nervous system, causing a decrease in the person’s activity level. They generally act on the GABA hormone, increasing its inhibitory action. Some types of psychotropic drugs included in this classification are used as sedatives, to facilitate sleep, while others are used to simply achieve physical and mental relaxation.
Within this group, we can find the following subtypes:
2.1 Barbiturates
This group of psychoactive drugs was the most popular until the discovery of benzodiazepines in the treatment of anxiety. However, the risk of these drugs is that they have a high addictive capacity, and overdose poisoning and even death is not uncommon. Also in the long run they can cause neurological damage.
2.2 Benzodiazepines
The discovery of this type of psychoactive drugs has greatly helped the treatment of anxiety disorders, presenting a series of benefits that the most commercialized psychoactive drugs for anxiety do today. Specifically, in addition to an immediate effect, they pose less of a health risk than barbiturates, produce fewer side effects, are less addictive, and cause less sedation.
In addition to their anxiolytic effect, benzodiazepines are used as sedatives and even as anticonvulsants . However, in prolonged treatments, they can generate dependence and withdrawal after cessation of consumption, so medical prescriptions must be strictly followed and correctly guide their intake and withdrawal.
It is a type of substance that favors the inhibitory function of GABA, being indirect agonists of this neurotransmitter. Although they are non-specifically distributed throughout the brain, the cortex and limbic system are where they perform best.
Within benzodiazepines there are also several types, depending on whether they are long-acting (they need more time to take effect, but have a much longer duration than the rest), intermediate or short-acting (immediate and short-term action, ideal for panic attacks), that is, depending on the half-life of the substance in the body.
Some examples of benzodiazepines are the well-known triazolam, alprazolam, lorazepam, clonacepam or bromazepam (better known by its trade name, Lexatine).
2.3 Short-acting hypnotic-sedative.
Zaleplom, Zolpidem and Zopiclone are the names of three drugs that, like benzodiazepines, act as GABA agonists . The main difference with benzodiazepines is that, although they act on all GABA receptors, hypnotics act only on receptors linked to sleep, not affecting cognition, memory or muscle function.
2.4 Buspirone
This psychoactive medication is used especially in cases of generalized anxiety disorder. Its mechanism of action focuses on serotonin, being its agonist. In this way, it is one of the few anxiolytics that are unrelated to GABA receptors. Does not cause addiction or withdrawal. However, it has the disadvantage that the effect of this substance can take more than a week to take effect.
3. Antidepressants
After anxiety disorders , mood disorders are some of the most prevalent in the general population , especially depression. To deal with this problem, we have this type of psychotropic drugs, which propose different alternatives. Of course, the exact mechanism by which they are useful in the treatment of certain disorders and not just mood swings is still unknown.
In any case, as with any other type of psychotropic medication, antidepressants can only be used on medical advice. The fact that they act mainly on mood does not mean that their influence on the brain does not carry considerable risks.
3.1 Mono Amino Oxidase Enzyme Inhibitors (MAOS)
The first antidepressants to be discovered, this type of psychoactive drug was accidentally found when looking for a medicine against tuberculosis . Its operation is based on the inhibition of the enzyme monoamine oxidase, normally responsible for the removal of excess monoamines (specifically serotonin, dopamine and norepinephrine).
This type of antidepressant tends not to be used as the treatment of choice, reserving cases that do not respond to other medications. The reason for this is that they present a high risk of hypertensive crisis, being necessary an exhaustive control of their administration and having to control that certain foods that contain tyramine or are rich in proteins (such as chocolate, dried fish, cheese, coffee, not are consumed) , beer …). It also has other side effects, such as possible anorgasmia or weight gain.
Within MAOIs can be found irreversible and non-selective (their function is to completely destroy the MAO enzyme) and reversible and selective that only inhibit the MAO function without destroying it, so if there is a real excess of monoamines, the enzyme can run Examples of MAOIs would be Isocarboxacid and Moclobemide.
3.2 Tricyclic and tetracyclic
Found when investigating the creation of neuroleptics, this type of psychotropic medication was until the discovery of SSRIs the most used in the treatment of depression . Its name comes from its ring-shaped structure. Its action is based on the inhibition of serotonin and noradrenaline reuptake, so that these hormones remain longer in the synaptic space, with a longer effect. The effects of these medications begin to be noticed after two or three weeks.
However, in addition to its effect on serotonin and noradrenaline, other hormones also affect it, being antagonists of acetylcholine, histamine and blocking some noradrenaline receptors. Therefore, they can cause antihistamine and anticholinergic effects (dry mouth, constipation, blurred vision…). They can also cause death by overdose, which must be regulated with special care.
Some famous tricyclic antidepressants are imipramine (used in conjunction with depression in anxiety disorders and parasomnias) or clomipramine (also used as a treatment in OCD and anorexia).
3.3 Specific serotonin reuptake inhibitors (SSRIs)
SSRIs are a type of psychotropic medication that are characterized, as the name implies, by specifically inhibiting serotonin reuptake . That is, preventing serotonin from being reabsorbed so that it becomes more available and prolongs its presence in the brain, without affecting other neurotransmitters.
In this group of psychotropic drugs, we find fluoxetine (the well-known Prozac), paroxetine, sertraline , fluvoxamine, citalopram and escitalopram.
It is the type of antidepressant with the highest level of safety and fewest side effects, being the first choice treatment in many cases, and not only in major depression, but also in other disorders. Specifically, they result in the pharmacological treatment of choice in OCD as well as eating disorders (fluoxetine is most effective in cases of bulimia).
3.4 Selective noradrenaline reuptake inhibitors
Like SSRIs, the action of this type of medication is based on inhibiting the reuptake of a hormone, so that it has a greater presence in neuronal synapses , in which case norepinephrine is the neurotransmitter in question. Reboxetine is the most relevant drug in this regard.
3.5 Dual serotonin and norepinephrine reuptake inhibitors
It acts in the same way as tricyclics, but with the difference that they only affect the neurotransmitters they are intended to act on . That is, they are specific, which eliminates many of the side effects. An example of this drug currently available is venlafaxine.
4. Mood Stabilizers / Eutimizers
Another major mood disorder is bipolar disorder . To maintain a balanced and stable mood, two basic types of psychotropic drugs are also available:
4.1 Lithium salts
Although it is proposed that it produces an alteration of the G protein that modulates the transmission of messages in neuronal synapses, the mechanism of action of this type of psychotropic drug is still not fully known. Despite the exact ignorance of the reason, this drug has shown high efficacy in the treatment of manic episodes and in maintaining a stable mood .
However, there is the disadvantage that the difference between the amount needed to produce a euthymizing effect and that needed for intoxication is very narrow, and control by analyzing the level of lithium in the blood is essential. It can also produce some side effects such as diarrhea, acne, tremor, hair loss or cognitive loss with some resistance to treatment.
4.2 Anticonvulsants
Although these drugs were developed to control seizures in cases of epilepsy, studies have shown that they are also very effective in treating bipolar disorder .
Its operation is based on favoring the action of GABA and reducing that of glutamate. Mainly, valproic acid, carbamazepine and topiramate are used.
