Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis, principally in schizophrenia but also in a range of other psychotic disorders. They are also the mainstay together with mood stabilizers in the treatment of bipolar disorder.
The atypical antipsychotics (AAP), also known as second generation antipsychotics (SGAs) and serotonin–dopamine antagonists (SDAs), are a group of antipsychotic drugs largely introduced after the 1970s and used to treat psychiatric conditions. Some atypical antipsychotics have received regulatory approval for schizophrenia, bipolar disorder, irritability in autism, and as an adjunct in major depressive disorder.
Quetiapine, sold under the brand name Seroquel among others, is an atypical antipsychotic medication used for the treatment of schizophrenia, bipolar disorder, and major depressive disorder. Despite being widely used as a sleep aid due to its sedating effect, the benefits of such use do not appear to generally outweigh the side effects. It is taken orally.
Aripiprazole, sold under the brand names Abilify and Aristada among others, is an atypical antipsychotic. It is primarily used in the treatment of schizophrenia and bipolar disorder. Other uses include as an add-on treatment in major depressive disorder, tic disorders and irritability associated with autism. It is taken by mouth or injection into a muscle. A Cochrane review found low-quality evidence of effectiveness in treating schizophrenia.
The dopamine hypothesis of schizophrenia or the dopamine hypothesis of psychosis is a model that attributes the positive symptoms of schizophrenia to a disturbed and hyperactive dopaminergic signal transduction. The model draws evidence from the observation that a large number of antipsychotics have dopamine-receptor antagonistic effects. The theory, however, does not posit dopamine overabundance as a complete explanation for schizophrenia. Rather, the overactivation of D2 receptors, specifically, is one effect of the global chemical synaptic dysregulation observed in this disorder.
Azapirones are a class of drugs used as anxiolytics, antidepressants, and antipsychotics. They are commonly used as add-ons to other antidepressants, such as selective serotonin reuptake inhibitors (SSRIs).
Flupentixol (INN), also known as flupenthixol, marketed under brand names such as Depixol and Fluanxol is a typical antipsychotic drug of the thioxanthene class. It was introduced in 1965 by Lundbeck. In addition to single drug preparations, it is also available as flupentixol/melitracen—a combination product containing both melitracen and flupentixol. Flupentixol is not approved for use in the United States. It is, however, approved for use in the UK, Australia, Canada, Russian Federation, South Africa, New Zealand, Philippines and various other countries.
Cyproheptadine, sold under the brand name Periactin among others, is a first-generation antihistamine with additional anticholinergic, antiserotonergic, and local anesthetic properties.
Tandospirone is an anxiolytic and antidepressant drug used in China and Japan, where it is marketed by Dainippon Sumitomo Pharma. It is a member of the azapirone class of drugs and is closely related to other azapirones like buspirone and gepirone.
In genetic epidemiology, endophenotype is a term used to separate behavioral symptoms into more stable phenotypes with a clear genetic connection. The concept was coined by Bernard John and Kenneth R. Lewis in a 1966 paper attempting to explain the geographic distribution of grasshoppers. They claimed that the particular geographic distribution could not be explained by the obvious and external "exophenotype" of the grasshoppers, but instead must be explained by their microscopic and internal "endophenotype".
Grandiose delusions (GD), also known as delusions of grandeur or expansive delusions, are a subtype of delusion that occur in patients with a wide range of psychiatric diseases, including two-thirds of patients in manic state of bipolar disorder, half of those with schizophrenia, patients with the grandiose subtype of delusional disorder, frequently in narcissistic personality disorder, and a substantial portion of those with substance abuse disorders. GDs are characterized by fantastical beliefs that one is famous, omnipotent, wealthy, or otherwise very powerful. The delusions are generally fantastic and typically have a religious, science fictional, or supernatural theme. There is a relative lack of research into GD, in contrast to persecutory delusions and auditory hallucinations. Around 10% of healthy people experience grandiose thoughts at some point in their lives but do not meet full criteria for a diagnosis of GD.
Altanserin is a compound that binds to the 5-HT2A receptor. Labeled with the isotope fluorine-18 it is used as a radioligand in positron emission tomography (PET) studies of the brain, i.e., studies of the 5-HT2A neuroreceptors. Besides human neuroimaging studies altanserin has also been used in the study of rats.
DASB, also known as 3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile, is a compound that binds to the serotonin transporter. Labeled with carbon-11 — a radioactive isotope — it has been used as a radioligand in neuroimaging with positron emission tomography (PET) since around year 2000. In this context it is regarded as one of the superior radioligands for PET study of the serotonin transporter in the brain, since it has high selectivity for the serotonin transporter.
WAY-100635 is a piperazine drug and research chemical widely used in scientific studies. It was originally believed to act as a selective 5-HT1A receptor antagonist, but subsequent research showed that it also acts as potent full agonist at the D4 receptor. It is sometimes referred to as a silent antagonist at the former receptor. It is closely related to WAY-100135.
Jeffrey H. Meyer is a scientist and professor working with mood and anxiety disorders using neuroimaging at the Department of Psychiatry, University of Toronto. He is currently the head of the Neurochemical Imaging Program in Mood and Anxiety Disorders in the Brain Health Imaging Centre at the Campbell Family Mental Health Research Institute and is working as a Senior Scientist in the General and Health Systems Psychiatry Division at the Centre for Addiction and Mental Health. He has also been awarded with the Tier 1 Canada Research Chair in the Neurochemistry of Major Depression.
Fananserin (RP-62203) is a drug which acts as a potent antagonist at both the 5HT2A receptor, and the Dopamine D4 receptor, but without blocking other dopamine receptors such as D2. It has sedative and antipsychotic effects, and has been researched for the treatment of schizophrenia, although efficacy was less than expected and results were disappointing.
5-I-R91150 is a compound that acts as a potent and selective antagonist of 5-HT2A receptors. Its main application is as its iodine-123 radiolabeled form, in which it can be used in SPECT scanning in human neuroimaging studies, to examine the distribution of the 5-HT2A receptor subtype in the brain, e.g. with respect to sex and age and in adults with Asperger syndrome or Alzheimer's disease.
Cariprazine, sold under the brand names Vraylar in the United States and Reagila in the European Union, is an atypical antipsychotic which is used in the treatment of schizophrenia, bipolar mania, and bipolar depression. It acts primarily as a D3 receptor and D2 receptor partial agonist, with high selectivity for the D3 receptor. Positive Phase III study results were published for schizophrenia and mania in early 2012, and for bipolar disorder I depression from a Phase II trial in 2015. It is also potentially useful as an add-on therapy in major depressive disorder.
The mechanisms of schizophrenia that underlie the development of schizophrenia, a psychiatric disorder, are complex and not clearly understood. A number of hypotheses including the dopamine hypothesis, and the glutamate hypothesis have been put forward in an attempt to explain the link between altered brain function and the symptoms and development of schizophrenia. Proposed models are separate from the proposed causes, which deal with the risk factors that may lead to schizophrenia.
Shitij Kapur FMedSci, has served as the 21st President and Principal of King's College London since 1 June 2021. Previously, he was the Dean of the Faculty of Medicine Dentistry and Health Sciences and Assistant Vice-Chancellor (Health) of the University of Melbourne from 2016 to 2020.
