Atypical Antipsychotics: Main Characteristics And Uses
Traditionally, the distinction has been used between typical antipsychotics and atypical or second-generation antipsychotics, such as quetiapine, olanzapine and risperidone; However, currently 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.
Atypical antipsychotics are a type of psychotropic drug that is used to treat different mental disorders, in particular schizophrenia and other similar problems, the use for which they were designed. Its main effects have to do with depression of the central nervous system, and therefore with sedation.
The term “atypical” is used to differentiate this class of antipsychotics from the classic ones, 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 neuroleptic malignant syndrome (characterized by muscle rigidity, fever, confusion and cardiac disorders that can cause death), tardive dyskinesia (involuntary movements of the face) or increased of diabetes risk.
When modern antipsychotics such as clozapine, olanzapine, risperidone, quetiapine, or aripiprazole, these drugs were promoted as safer than existing neuroleptic drugs. In particular, the lower risk of suffering from extrapyramidal symptoms such as parkinsonism, tardive dyskinesia and akathisia was highlighted.
However, recent research suggests that there are no particularly significant differences between typical and atypical antipsychotics in terms of the severity of side effects, nor in the degree of effectiveness or mechanism of action. In this sense, it has been proposed that it is more useful to distinguish between individual drugs.
In any case, it does seem that typical antipsychotics cause parkinsonian-like symptoms more frequently, while atypical ones are associated to a greater extent with weight gain and consequently with the risk of developing type 2 or non-insulin-dependent diabetes mellitus.
What are these medications used for?
Atypical antipsychotics are primarily used 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 they are not first-line drugs.
1. Schizophrenia
The extensive body of research that has been developed over the decades surrounding the effectiveness of neuroleptics reveals that atypical antipsychotics are effective in reducing the positive symptoms of schizophrenia (mainly hallucinations and delusions), but fail to treat negative symptoms such as emotional flattening
In any case, in many cases of schizophrenia and other disorders on the psychosis spectrum it is necessary to administer this type of drugs to avoid serious symptoms. Even so, the effectiveness rate of antipsychotics is not complete, since 20% of patients do not respond adequately and 30-40% do so only partially.
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, medications such as olanzapine and quetiapine are used as adjuvant therapy to the drugs of choice: mood stabilizers, among which lithium and valproic acid or valproate stand out. Atypical antipsychotics are only recommended if symptoms are severe and the main treatment is insufficient.
3. Dementia
Antipsychotics are prescribed in some cases of dementia if there are significant psychotic symptoms (such as delusions) and especially if severe psychomotor agitation occurs; These types of alterations facilitate the appearance of aggressive or interfering behaviors, which can become truly problematic for caregivers and the person.
It is important to mention that it has been detected an increased risk of heart problems, strokes and overall mortality in elderly patients with dementia treated with antipsychotics, particularly typical ones. Quetiapine, which is included in the atypical group, 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, sleeping problems… In these cases, psychostimulants and antidepressants are also prescribed.
