A GABA receptor agonist is a drug that is an

agonist An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an R ...

for one or more of the GABA receptors, producing typically

sedative A sedative or tranquilliser is a substance that induces sedation by reducing irritability or Psychomotor agitation, excitement. They are central nervous system (CNS) Depressant, depressants and interact with brain activity, causing its decelera ...

effects, and may also cause other effects such as

anxiolytic An anxiolytic (; also antipanic or anti-anxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxie ...

anticonvulsant Anticonvulsants (also known as antiepileptic drugs, antiseizure drugs, or anti-seizure medications (ASM)) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also used in the treatme ...

, and

muscle relaxant A muscle relaxant is a drug that affects skeletal muscle function and decreases the muscle tone. It may be used to alleviate symptoms such as muscle spasms, pain, and hyperreflexia. The term "muscle relaxant" is used to refer to two major therapeu ...

effects. There are three receptors of the ''gamma''-aminobutyric acid. The two receptors GABA-α and GABA-ρ are ion channels that are permeable to chloride ions which reduces neuronal excitability. The GABA-β receptor belongs to the class of G-Protein coupled receptors that inhibit adenylyl cyclase, therefore leading to decreased cyclic adenosine monophosphate (cAMP). GABA-α and GABA-ρ receptors produce sedative and hypnotic effects and have anti-convulsion properties. GABA-β receptors also produce similar effects. Furthermore, they lead to changes in gene transcription, and are mainly found in autonomic nervous system centers.

Types

Many commonly used

and

drugs that affect the GABA receptor complex are not agonists. These drugs act instead as positive allosteric modulators (PAMs) and while they do bind to the GABA receptors, they bind to an allosteric site on the receptor and cannot induce a response from the neuron without an actual agonist being present. Drugs that fall into this class exert their pharmacodynamic action by increasing the effects that an agonist has when potentiation is achieved. General anaesthetics act primarily as PAMs of GABA-A receptor. Positive allosteric modulators work by increasing the frequency with which the chloride channel opens when an agonist binds to its own site on the GABA receptor. The resulting increase in the concentration of Cl− ions in the postsynaptic neuron immediately hyperpolarizes this neuron, making it less excitable and thus inhibiting the possibility of an

action potential An action potential (also known as a nerve impulse or "spike" when in a neuron) is a series of quick changes in voltage across a cell membrane. An action potential occurs when the membrane potential of a specific Cell (biology), cell rapidly ri ...

. However, some general anaesthetics like propofol and high doses of barbiturates may not only be positive allosteric modulators of GABA-A receptors but also direct agonists of these receptors.

Alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...

is an indirect

GABA GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ...

agonist. GABA is the major inhibitory

neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotra ...

in the brain, and GABA-like drugs are used to suppress spasms. Alcohol is believed to mimic GABA's effect in the brain, binding to GABA receptors and inhibiting neuronal signaling.

GABA_A

GABA_A receptor ligands include:

Agonists

* Abecarnil *

Barbiturate Barbiturates are a class of depressant, depressant drugs that are chemically derived from barbituric acid. They are effective when used medication, medically as anxiolytics, hypnotics, and anticonvulsants, but have physical and psychological a ...

s (in high doses) *

Etomidate Etomidate (United States Adopted Name, USAN, International Nonproprietary Name, INN, British Approved Name, BAN; marketed as Amidate) is a short-acting intravenous anaesthetic agent used for the induction of general anaesthesia and sedation for ...

* Eszopiclone * Bamaluzole * Fengabine *

* Gabamide * GABOB * Gaboxadol *

Ibotenic acid Ibotenic acid or (''S'')-2-amino-2-(3-hydroxyisoxazol-5-yl)acetic acid, also referred to as ibotenate, is a naturally occurring alpha-amino acid found in certain ''Amanita'' mushrooms, that primarily acts as a potent glutamate receptor agonist ...

* Isoguvacine * Isonipecotic acid * Muscimol *

Phenibut Phenibut, sold under the brand name Anvifen among others, is a central nervous system (CNS) depressant with anxiolytic effects, and is used to treat anxiety, insomnia, and for a variety of other indications. It is usually taken oral administrat ...

* Picamilon * Progabide *

Propofol Propofol is the active component of an intravenous anesthetic formulation used for induction and maintenance of general anesthesia. It is chemically termed 2,6-diisopropylphenol. The formulation was approved under the brand name Diprivan. Nu ...

* Quisqualamine * SL 75102 * Thiomuscimol * Topiramate *

Zolpidem Zolpidem, sold under the brand name Ambien among others, is a medication primarily used for the short-term treatment of sleeping problems. Guidelines recommend that it be used only after cognitive behavioral therapy for insomnia and after beh ...

* Zopiclone

PAMs

s (e.g.,

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

isopropanol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable, organic compound with a pungent alcoholic odor. Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, an ...

) * Avermectins (e.g.,

ivermectin Ivermectin is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, it is used to treat infestations including head lice ...

) *

s (e.g.,

phenobarbital Phenobarbital, also known as phenobarbitone or phenobarb, sold under the brand name Luminal among others, is a medication of the barbiturate type. It is recommended by the World Health Organization (WHO) for the treatment of certain types of ...

) *

Benzodiazepine Benzodiazepines (BZD, BDZ, BZs), colloquially known as "benzos", are a class of central nervous system (CNS) depressant, depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed t ...

s (e.g.,

diazepam Diazepam, sold under the brand name Valium among others, is a medicine of the benzodiazepine family that acts as an anxiolytic. It is used to treat a range of conditions, including anxiety disorder, anxiety, seizures, alcohol withdrawal syndr ...

alprazolam Alprazolam, sold under the brand name Xanax among others, is a fast-acting, potent tranquilizer of moderate duration within the triazolobenzodiazepine group of chemicals called benzodiazepines. Alprazolam is most commonly prescribed in the ...

) * Bromides (e.g.,

potassium bromide Potassium bromide ( K Br) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the US. Its action is due to the bromide ion ( sodium bromide is equa ...

) *

Carbamate In organic chemistry, a carbamate is a category of organic compounds with the general Chemical formula, formula and Chemical structure, structure , which are formally Derivative (chemistry), derived from carbamic acid (). The term includes orga ...

s (e.g., meprobamate,

carisoprodol Carisoprodol, sold under the brand name Soma among others, is an oral medication used for musculoskeletal pain. Effects generally begin within half an hour and last for up to six hours. Common side effects include headache, dizziness, and s ...

) *

Chloral hydrate Chloral hydrate is a geminal diol with the formula . It was first used as a sedative and hypnotic in Germany in the 1870s. Over time it was replaced by safer and more effective alternatives but it remained in use in the United States until at ...

, chloralose, petrichloral, and other 2,2,2-trichloroethanol

prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ...

s * Chlormezanone * Clomethiazole * Dihydroergolines (e.g., ergoloid (dihydroergotoxine)) * Etazepine * Etifoxine * 2-Substituted

phenols In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (− O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds ar ...

(e.g.,

thymol Thymol (also known as 2-isopropyl-5-methylphenol, IPMP), , is a toxic monoterpenoid phenol derivative of ''p''-Cymene, isomeric with carvacrol. It occurs naturally in the oil of thyme, and it is extracted from ''Thymus vulgaris'' (common thy ...

eugenol Eugenol is an allyl chain-substituted guaiacol, a member of the allylbenzene class of chemical compounds. It is a colorless to pale yellow, aromatic oily liquid extracted from certain essential oils especially from clove, nutmeg, cinnamon, ...

) *

Imidazole Imidazole (ImH) is an organic compound with the formula . It is a white or colourless solid that is soluble in water, producing a mildly alkaline solution. It can be classified as a heterocycle, specifically as a diazole. Many natural products, ...

s (e.g.,

etomidate Etomidate (United States Adopted Name, USAN, International Nonproprietary Name, INN, British Approved Name, BAN; marketed as Amidate) is a short-acting intravenous anaesthetic agent used for the induction of general anaesthesia and sedation for ...

) *

Kavalactone Kavalactones are a class of lactone compounds found in kava roots and ''Alpinia zerumbet'' (shell ginger) and in several Gymnopilus, Phellinus and Inonotus fungi. Some kavalactones are bioactive. They are responsible for the psychoactive, analges ...

s (found in

kava Kava or kava kava (''Piper methysticum'': Latin 'pepper' and Latinized Ancient Greek, Greek 'intoxicating') is a plant in the Piperaceae, pepper family, native to the Pacific Islands. The name ''kava'' is from Tongan language, Tongan and Marqu ...

) * Loreclezole * Neuroactive steroids (e.g.,

allopregnanolone Allopregnanolone is a natural product, naturally occurring neurosteroid which is made in the body from the hormone progesterone. As a medication, allopregnanolone is referred to as brexanolone, sold under the brand name Zulresso, and used to t ...

, ganaxolone) *

Nonbenzodiazepine Nonbenzodiazepines (), sometimes referred to colloquially as Z-drugs (as many of their names begin with the letter "z"), are a class of psychoactive, depressant, sedative, hypnotic, anxiolytic drugs that are benzodiazepine-like in uses, such as f ...

s (e.g., zaleplon,

zolpidem Zolpidem, sold under the brand name Ambien among others, is a medication primarily used for the short-term treatment of sleeping problems. Guidelines recommend that it be used only after cognitive behavioral therapy for insomnia and after beh ...

, zopiclone, eszopiclone) *

* Piperidinediones (e.g., glutethimide, methyprylon) * Propanidid *

Pyrazolopyridine The pyrazolopyridines are a group of drugs investigated as anxiolytics which act as positive allosteric modulators of the GABAA receptor, GABAA receptor via the barbiturate binding site. They include the following compounds: * Cartazolate (SQ-65 ...

s (e.g., etazolate) *

Quinazolinone Quinazolinone is a heterocyclic chemical compound, a quinazoline with a carbonyl group in the C4N2 ring. Two isomers are possible: 2-quinazolinone and 4-quinazolinone, with the 4-isomer being the more common. These compounds are of interest in ...

s (e.g.,

methaqualone Methaqualone is a hypnotic sedative. It was sold under the brand names Quaalude ( ) and Sopor among others, which contained 300 mg of methaqualone, and sold as a combination drug under the brand name Mandrax, which contained 250 mg me ...

) * Skullcap constituents (e.g.,

Baicalein Baicalein (5,6,7-trihydroxyflavone) is a flavone, a type of flavonoid, originally isolated from the roots of '' Scutellaria baicalensis'' and '' Scutellaria lateriflora''. It is also a constituent of '' Oroxylum indicum'' (Indian trumpetflower) ...

) *

Stiripentol Stiripentol, sold under the brand name Diacomit, is an anticonvulsant medication used for the treatment of Dravet syndrome - a serious genetic brain disorder. The most common side effects include loss of appetite, weight loss, insomnia (difficu ...

* Disulfonylalkanes (e.g., sulfonmethane, tetronal, trional) * Valerian constituents (e.g.,

valeric acid Valeric acid or pentanoic acid is a straight-chain alkyl carboxylic acid with the chemical formula . Like other low-molecular-weight carboxylic acids, it has an unpleasant odor. It is found in the perennial flowering plant '' Valeriana offici ...

, valerenic acid) *

Volatile organic compounds Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. They are common and exist in a variety of settings and products, not limited to house mold, upholstered furniture, arts and crafts sup ...

(e.g.,

chloroform Chloroform, or trichloromethane (often abbreviated as TCM), is an organochloride with the formula and a common solvent. It is a volatile, colorless, sweet-smelling, dense liquid produced on a large scale as a precursor to refrigerants and po ...

diethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...

sevoflurane Sevoflurane, sold under the brand name Sevorane, among others, is a sweet-smelling, nonflammable, highly fluorinated methyl isopropyl ether used as an inhalational anaesthetic for induction and maintenance of general anesthesia. After desflu ...

)