Azaperone is a pyridinylpiperazine and butyrophenone

neuroleptic Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of oth ...

drug A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhal ...

with

sedative A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but ...

and

antiemetic An antiemetic is a drug that is effective against vomiting and nausea. Antiemetics are typically used to treat motion sickness and the side effects of opioid analgesics, general anaesthetics, and chemotherapy directed against cancer. The ...

effects, which is used mainly as a

tranquilizer A tranquilizer is a drug that is designed for the treatment of anxiety, fear, tension, agitation, and disturbances of the mind, specifically to reduce states of anxiety and tension. Etymology Tranquilizer, as a term, was first used by F.F. Yonk ...

veterinary Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in animals. Along with this, it deals with animal rearing, husbandry, breeding, research on nutri ...

medicine. It is uncommonly used in humans as an

antipsychotic Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range o ...

drug. Azaperone acts primarily as a

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 8 ...

antagonist but also has some antihistaminic and

anticholinergic Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system. These agents inhibit the parasympathetic nervous syste ...

properties as seen with similar drugs such as

haloperidol Haloperidol, sold under the brand name Haldol among others, is a typical antipsychotic medication. Haloperidol is used in the treatment of schizophrenia, tics in Tourette syndrome, mania in bipolar disorder, delirium, agitation, acute psychos ...

. Azaperone may cause

hypotension Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dia ...

and while it has minimal effects on respiration in pigs, high doses in humans can cause

respiratory depression Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide ( hypercapn ...

Veterinary use

The most common use for azaperone is in relatively small doses as a " serenic" (to reduce aggression) in farmed pigs, either to stop them fighting or to encourage sows to accept piglets. Higher doses are used for

anesthesia Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prevention of pain), paralysis (muscle relaxation), a ...

in combination with other drugs such as

xylazine Xylazine is a pharmaceutical drug used for sedation, anesthesia, muscle relaxation, and analgesia in animals such as horses, cattle, and other non-human mammals. Veterinarians also use xylazine as an emetic, especially in cats. It is an analog o ...

, tiletamine and zolazepam. Azaperone is also used in combination with strong narcotics such as

etorphine Etorphine (M99) is a semi-synthetic opioid possessing an analgesic potency approximately 1,000–3,000 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather the r ...

carfentanil Carfentanil or carfentanyl, sold under the brand name Wildnil, is a very potent opioid analgesic which is used in veterinary medicine to anesthetize large animals such as elephants and rhinoceroses. It is typically administered in this contex ...

for tranquilizing large animals such as elephants. Use in horses is avoided as adverse reactions may occur. The European Medicines Agency has established a

maximum residue limit The maximum residue limit (also maximum residue level, MRL), is the maximum amount of pesticide residue that is expected to remain on food products when a pesticide is used according to label directions, that will not be a concern to human health. ...

for azaperone when administered to pigs. Azaperone (under the brand name Stresnil) was approved for use in pigs in the USA in 1983, under NADA 115-732.

Synthesis

The alkylation of 2-chloropyridine (1) with

piperazine Piperazine () is an organic compound that consists of a six-membered ring containing two nitrogen atoms at opposite positions in the ring. Piperazine exists as small alkaline deliquescent crystals with a saline taste. The piperazines are a broad ...

gives 1-(pyridin-2-yl)piperazine

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(2). The attachement of the sidechain by reaction with 4-chloro-4'-fluorobutyrophenone 874-54-2(3) completed the synthesis of azaperone (4).

References

{{Piperazines Butyrophenone antipsychotics Piperazines 2-Pyridyl compounds Typical antipsychotics

Veterinary use

Synthesis

See also

References