Butyrophenones: characteristics of atypical antipsychotics.

A summary of the characteristics of this group of antipsychotics used in the clinical setting.

The discovery of the first antipsychotic in the early 1950s, chlorpromazine, was a major revolution in the treatment of psychoses, especially schizophrenia.

In this article we will discuss one family of antipsychotics: the butyrophenones.. Within it we find haloperidol (especially known for its usefulness in schizophrenia) and droperidol.

History: the first antipsychotic

The beginning of butyrophenone research starts with chlorpromazine.

Chlorpromazine was synthesized as an antihistamine by the French pharmaceutical industry and in 1950, Henri Laborit, a French surgeon, noted its sedative effect in psychotic patients. Two years later, in 1952, Delay, Deniker and Harl tested it at the Sainte Anne Hospital in Paris and confirmed its usefulness for positive psychotic symptoms of schizophrenia. confirmed its usefulness for the positive psychotic symptoms of schizophrenia..

Since the introduction of the first typical antipsychotic, research on neuroleptics has focused on increasing their efficacy in schizophrenia, reducing the negative symptoms of the disorder and defining their mechanism of action.

Typical and atypical antipsychotics

Typical or first-generation antipsychotics have more side effects than second-generation or atypical antipsychotics. The latter appeared with the discovery of Clozapine in the 1970s, which began to be marketed in Switzerland and Austria.

Today, second generation or atypical antipsychotics already exist.They also act on the negative symptoms of schizophrenia (something that the first generation drugs did not do), in addition to the positive symptoms.

Their antipsychotic efficacy is similar to that of the typical ones, and they differ from them in having a lower incidence of EPS (Extrapyramidal Syndrome: set of motor symptoms) and hyperprolactinemia. (side or adverse effects).

Butyrophenones

Butyrophenones are a family of atypical antipsychotics. Antipsychotics are a class of medications or drugs used to treat schizophrenia and other psychotic disorders, as well as bipolar disorder, among others.

In general, antipsychotics reduce dopamine (DA), a neurotransmitter in the brain that is abnormally abnormally elevated in psychotic disorders.

Droperidol

One of the butyrophenone-type antipsychotics is Droperidol, very short-acting and strongly sedative and tranquilizing..

Droperidol has a high antiemetic activity (prevents vomiting and nausea). It acts as a dopamine receptor antagonist, being partially selective for D2 receptors.

Its antiemetic action is produced by antagonism of DA receptors in a very specific area of the vagus nerve. It is especially useful for the prevention and treatment of postoperative and/or opioid analgesic-induced nausea and vomiting.

It also exhibits weak cholinergic (acetylcholine) cholinergic receptor antagonist activity. (acetylcholine) muscarinic receptors. Acetylcholine is a neurotransmitter involved in the transmission of nerve impulses and movement.

Features

Droperidol is used for the prevention and treatment of postoperative nausea and vomiting in adults, and as a second-line treatment in children and adolescents. Also for vomiting and nausea induced by morphine derivatives.

As for the route of administration of this type of butyrophenone, it is administered intravenously.

Some of its contraindications are: cases of hypersensitivity to the drug or Allergy to butyrophenones, bradykinesia (decrease in normal heart rate) and Parkinson's disease.

Precautions

It should be taken into account that it is a drug that can increase CNS depression produced by other depressant drugs. In addition, caution should be exercised caution should be taken in cases of epilepsy, hypotension, cardiac arrhythmias and chronic alcoholism, among others.among others. The appearance of unexplained fever may be a symptom of neuroleptic malignant syndrome.

The dose in the elderly should be reduced, as well as in those subjects with renal and/or hepatic insufficiency. In patients with breast cancer or prolactin-dependent tumors, it can raise prolactin levels.

Haloperidol: another butyrophenone type

Another of the butyrophenone-type neuroleptics is Haloperidol.

It acts in the same way as the previous one, so it is also a potent antagonist of brain dopaminergic receptors. It is classified among the high potency neuroleptics.. It has neither antihistaminic nor anticholinergic activity (therefore, it has no side effects of these two types).

The therapeutic indications of haloperidol are diverse. As a neuroleptic it is used in:

• Delusions and hallucinations (schizophrenia, Korsakoff's syndrome...).
• Personality disorder: paranoid, schizoid, schizotypal, borderline, etc....

As treatment of psychomotor agitation, some of its uses are for:

• Mania, dementia, intellectual disability, alcoholism.
• Personality disorders.
• Agitation, aggressiveness.
• Behavioral disorders.
• Tics, stuttering, symptoms of Tourette's syndrome...

Like Droperidol, as an antiemetic it prevents vomiting and nausea of different etiology.

It is contraindicated in cases of hypersensitivity to the drug, coma, depression of the central nervous system by alcohol or other depressants, Parkinson's and basal ganglia lesion.

Bibliographic references:

• Ortiz, A., De la Mata, I. (2001). New antipsychotics, 25(1), 1-8. National Health System.
• Consejo General de Colegios Oficiales de Farmacéuticos. (2012). Catalog of Medicines. Consejo Collection.
• Inchauspe, J.A. and Valverde, M.A. (2018). Believing in clozapine: faith and evidence. Rev. Asoc. esp. neuropsiq, 38(133), 239-262.