Atypical antipsychotics: characteristics and main uses

Traditionally, the distinction between typical antipsychotics and atypical or second-generation antipsychotics, such as quetiapine, olanzapine, and risperidone, has been used; however, at present the usefulness of this dichotomy is highly questioned in the scientific community in general.

In this article we will analyze the main characteristics and uses of atypical antipsychotics. We will particularly emphasize the distinction between these drugs and typical neuroleptics.

• Related article: "Types of antipsychotics (or neuroleptics)"

What are atypical antipsychotics?

Atypical antipsychotics are a type of psychotropic drug used to treat various mental disorders, in particular the schizophrenia and other similar problems, the use for which they were designed. Its main effects have to do with central nervous system depression, and therefore sedation.

The term "atypical" is used to differentiate this class of antipsychotics from the classics, currently known as "typical." However, the distinction between the two categories of drugs is blurred and there is debate about their wisdom and usefulness; We will dedicate the following section to this aspect.

Antipsychotic medications reduce the symptoms of psychosis and other disorders by inhibition of dopaminergic activity in brain pathways. Some atypical antipsychotics also interact with serotonin and norepinephrine receptors, neurotransmitters that are part of the pharmacological class of amines, such as dopamine.

Among the most common side effects and adverse reactions of atypical antipsychotics we find the neuroleptic malignant syndrome (characterized by rigidity muscle, fever, confusion and heart disorders that can lead to death), tardive dyskinesia (involuntary movements of the face) or increased risk of diabetes.

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Differences from typical antipsychotics

When modern antipsychotics like clozapine, olanzapine, risperidone, quetiapine, or aripiprazole, these drugs were touted as safer than the neuroleptic drugs that already existed. In particular, the lower risk of suffering extrapyramidal symptoms such as parkinsonism, tardive dyskinesia and akathisia stood out.

However, recent research suggests that there are no particularly significant differences between typical antipsychotics. and atypicals in terms of the severity of side effects, as well as in the degree of efficacy or in the mechanism of action. In this sense, it has been proposed that it is more useful to distinguish between individual drugs.

If anything, it does seem that typical antipsychotics cause parkinsonian-like symptoms more frequently, while atypicals are associated to a greater extent with weight gain and consequently the risk of developing type 2 or non-insulin-dependent diabetes mellitus.

What are these medicines used for?

Atypical antipsychotics are used primarily to treat schizophrenia and bipolar disorder, two of the mental disorders most associated with psychotic symptoms. They are also occasionally prescribed in cases of autism, dementia, generalized anxiety disorder, or obsessive-compulsive disorder, but these are not first-line drugs.

1. Schizophrenia

The vast body of research that has developed over the decades on the effectiveness of neuroleptics reveals that neuroleptics Atypical antipsychotics are effective in reducing the positive symptoms of schizophrenia (mainly hallucinations and delusions), but fail to treat negative symptoms such as affective flattening.

In any case, in many cases of schizophrenia and other psychosis spectrum disorders it is necessary to administer these types of drugs to avoid serious symptoms. Even so, the efficacy rate of antipsychotics is not complete, since 20% of patients do not respond adequately and 30-40% do so only partially.

2. Bipolar disorder

In its classic form, bipolar disorder is characterized by the alternation between periods in which the mood is very low and others in which it is pathologically high; In other words, episodes of depression and mania occur. Atypical antipsychotics are sometimes used to manage symptoms of manic and mixed episodes.

In these cases, drugs such as olanzapine and quetiapine are used as adjunctive therapy to the drugs. of choice: mood stabilizers, among which lithium and valproic acid or valproate. Atypical antipsychotics are only recommended if the symptoms are severe and the main treatment is insufficient.

• Related article: "Bipolar Disorder: 10 characteristics and curiosities that you did not know"

3. Dementia

Antipsychotics are prescribed in some cases of dementia if there are significant psychotic symptoms (such as delusions) and especially if there is severe psychomotor agitation; these types of alterations facilitate the appearance of aggressive or interfering behaviors, which can become truly problematic for caregivers and for the person.

It is important to mention that it has been detected an increased risk of heart problems, strokes and mortality in general in elderly patients with dementia treated with antipsychotics, particularly the typical ones. Quetiapine, which is included in the group of atypicals, appears to be safer than other neuroleptics.

4. Autism

Atypical antipsychotics such as risperidone and aripiprazole have been approved in some countries as treatments for certain characteristic symptoms of autism spectrum disorders: agitation, irritability, aggressiveness, repetitive behaviors, trouble sleeping... In these cases, psychostimulants and antidepressants are also prescribed.

• Related article: "The 4 types of Autism and their characteristics"