Schizophrenia and other such psychotic disorders are old acquaintances for psychology and medicine. Different researchers have proposed various ways of understanding this type of disorder, which generates profound suffering in the person who suffers it and in his or her environment, as well as looking for different ways of treating them.

Different types of substances have been used in psychopharmacology to deal with this problem and the symptoms shown by those who suffer from it: antipsychotics or neuroleptics. One of these psychopharmaceuticals is olanzapine .

Psychotic disorders and dopamine

So-called psychotic disorders are a group of mental disorders in which strange and implausible perceptions and ideas appear and usually a certain loss of contact with reality.

Within this type of disorder, among which schizophrenia stands out , there appear both symptoms that add elements to the individual’s behaviour or positive symptoms (the characteristic example being hallucinations) and those that cause a decrease in the individual’s abilities (such as alogia or cognitive impairment) or negative symptoms

At a neuropsychological level, it is observed that the presence of symptoms of this type are usually linked to problems in the synthesis and uptake of the neurotransmitter known as dopamine. Positive symptoms are associated with an excess of dopaminergic activity in the mesolimbic pathway, while negative symptoms tend to be linked to the presence of deficit or absence of dopamine in the mesocortical pathway .

In this sense, we have tried to find substances and active ingredients that allow a change in the synthesis and reuptake of dopamine in these areas.

A Brief History of Neuroleptics

Throughout history, numerous substances and compounds have been found and researched whose active ingredients allow a reduction of the psychotic symptoms present in schizophrenia and other similar disorders.

The first substances of this type were found by chance, but they provided a great advantage to patients with this disorder by allowing their treatment. These are the classic or typical neuroleptics. Their main mechanism of action is on the dopamine D2 receptor, which they block indiscriminately throughout the brain.

This causes positive symptoms such as hallucinations to be greatly diminished by decreasing the level of dopamine in the mesolimbic pathway. However, by acting throughout the brain and not only in the mesolimbic pathway, they easily generate different side effects, and do not have a therapeutic effect on negative symptoms. In fact, by further decreasing the level of dopamine in the mesocortical pathway, they may even worsen them.

The low effectiveness in negative symptoms and the presence of side effects that can be severe led to further research into safer and more effective substances. This research resulted in the creation of the atypical antipsychotics or neuroleptics. And within this group, we can find olanzapine.

Olanzapine as an atypical neuroleptic

Olanzapine is one of the main atypical neuroleptics, substances used to reduce the symptoms of schizophrenia and other psychotic disorders. It is a substance derived from dibenzothiazepines, which is marketed in tablet and capsule form.

As an atypical neuroleptic, the main mechanism of action of olanzapine is based on the blockade of the dopamine D2 receptors, but this time an anti-serotoninergic effect is also produced.

Since serotonin has an inhibitory effect on dopamine synthesis and release, introducing a component that limits the release of serotonin causes overall dopamine levels to remain stable in most nerve pathways. In this way, although it continues to have a great effect on the mesolimbic pathway that allows the positive symptoms of schizophrenia to be combated, it does not generate a destabilization of other pathways.

In addition, the fact that the cortex contains a large number of serotonergic receptors causes the level of dopamine in the mesocortical pathway to increase as its action is limited, which also makes it possible to combat some of the negative symptoms.

In this way, olanzapine and other similar substances make it possible to combat both the positive and negative symptoms of schizophrenia more efficiently and more safely than classical antipsychotics, generating fewer secondary symptoms and making them less severe.

In what disorders is it used?

The main use of Olanzapine is in the treatment of psychotic-type disorders and especially schizophrenia. However, the properties of this substance have made it valid for the treatment of other psychic problems.

Specifically, it is used to combat manic episodes in bipolar disorder. It has also been used occasionally in some cases of borderline personality disorder.

Side effects and contraindications of olanzapine

Like all drugs, olanzapine can generate various side effects of varying intensity and may be contraindicated in some cases. This occurs because olanzapine affects some parts of the body in a way that goes beyond the therapeutic mechanisms by which it is intended to mitigate the symptoms of the disorder to be treated; something that is inevitable considering that the active ingredient is not “remote controlled”, but rather is a molecule that interacts with everything it encounters. These unexpected ways of influencing the human body bring out the side effects.

One of the most frequent secondary symptoms caused by this substance is increased appetite and weight gain . It can also lead to hyperglycemia, increased triglyceride levels and even diabetes, or greatly harm those who suffer from it if doses are not controlled and monitored.

It is also very common for olanzapine to generate a certain level of drowsiness or sedation, as well as excessive salivation, tachycardia (which is why it is not recommended for patients with heart problems), hypotension, muscle weakness and dizziness . Nausea and vomiting are also a possible side effect, as well as constipation. Finally, it can also lead to a decrease in libido and erectile capacity.

Other not so common symptoms are the presence of tardive dyskinesia (uncontrolled movements of mouth and tongue. Fever, allergy, seizures, changes in visual perception or swelling of parts of the body may also occur.

It is also contraindicated in those patients who have suffered cerebral infarctions or are in the process of dementia. Patients with diabetes, liver, pancreas or heart problems should not take this antipsychotic. In the case of pregnant women, olanzapine can cause problems in the foetus , so the doctor should be consulted about possible alternatives or ways of proceeding.

Price

The price of olanzapine, for a box of 28 tablets of 5 milligrams, is about 26 euros, and about 575 Mexican pesos in Mexico.

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