M03A
Muscle relaxants 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 therape ...
, peripherally acting agents

M03AA
Curare Curare ( /kʊˈrɑːri/ or /kjʊˈrɑːri/; ''koo-rah-ree'' or ''kyoo-rah-ree'') is a common name for various alkaloid arrow poisons originating from plant extracts. Used as a paralyzing agent by indigenous peoples in Central and Sout ...
alkaloids

:M03AA01

Alcuronium Alcuronium chloride (formerly marketed as Alloferin) is a neuromuscular blocking (NMB) agent, alternatively referred to as a skeletal muscle relaxant. It is a semi-synthetic substance prepared from C- toxiferine I, a ''bis''-quaternary alkaloid ...

:M03AA02

Tubocurarine Tubocurarine (also known as ''d''-tubocurarine or DTC) is a toxic alkaloid historically known for its use as an arrow poison. In the mid-1900s, it was used in conjunction with an anesthetic to provide skeletal muscle relaxation during surgery or ...

:M03AA04 Dimethyltubocurarine

M03AB
Choline Choline is an essential nutrient for humans and many other animals. Choline occurs as a cation that forms various salts (X− in the depicted formula is an undefined counteranion). Humans are capable of some ''de novo synthesis'' of choline but ...
derivatives

:M03AB01

Suxamethonium Suxamethonium chloride, also known as suxamethonium or succinylcholine, or simply sux by medical abbreviation, is a medication used to cause short-term paralysis as part of general anesthesia. This is done to help with tracheal intubation or ele ...

M03AC Other
quaternary ammonium compounds In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium ca ...

:M03AC01

Pancuronium Pancuronium (trademarked as Pavulon) is an aminosteroid muscle relaxant with various medical uses. It is used in euthanasia and is used in some states as the second of three drugs administered during lethal injections in the United States. Me ...

:M03AC02

Gallamine Gallamine triethiodide (Flaxedil) is a non-depolarising muscle relaxant. It acts by combining with the cholinergic receptor sites in muscle and competitively blocking the transmitter action of acetylcholine. Gallamine is a non-depolarising type o ...

:M03AC03

Vecuronium Vecuronium bromide, sold under the brand name Norcuron among others, is a medication used as part of general anesthesia to provide skeletal muscle relaxation during surgery or mechanical ventilation. It is also used to help with endotracheal ...

:M03AC04

Atracurium Atracurium besilate, also known as atracurium besylate, is a medication used in addition to other medications to provide skeletal muscle relaxation during surgery or mechanical ventilation. It can also be used to help with endotracheal intubati ...

:M03AC05

Hexafluronium Hexafluronium (or hexafluorenium) is a muscle relaxant. It acts as a nicotinic acetylcholine receptor Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic recep ...

:M03AC06

Pipecuronium bromide Pipecuronium (Arduan) is a bisquaternary aminosteroid muscle relaxant which blocks nicotinic acetylcholine receptors at the neuromuscular junction. It is also an antagonist of M2 and M3 muscarinic receptors The muscarinic acetylcholine re ...

:M03AC07

Doxacurium chloride Doxacurium chloride (formerly recognized as BW938U80 or BW A938U) is a neuromuscular-blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in anesthesia to provide skeletal ...

:M03AC08

Fazadinium bromide Fazadinium bromide is a muscle relaxant which acts as a nicotinic acetylcholine receptor antagonist through neuromuscular A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. ...

:M03AC09

Rocuronium bromide Rocuronium bromide (brand names Zemuron, Esmeron) is an aminosteroid non-depolarizing neuromuscular blocker or muscle relaxant used in modern anaesthesia to facilitate tracheal intubation by providing skeletal muscle relaxation, most commonly ...

:M03AC10 Mivacurium chloride :M03AC11

Cisatracurium Cisatracurium besilate (INN; cisatracurium besylate ( USAN); formerly recognized as 51W89; trade name Nimbex) is a bisbenzyltetrahydroisoquinolinium that has effect as a neuromuscular-blocking drug non-depolarizing neuromuscular-blocking drugs, ...

M03AX Other muscle relaxants, peripherally acting agents

:M03AX01

Botulinum toxin Botulinum toxin, or botulinum neurotoxin (BoNT), is a neurotoxic protein produced by the bacterium ''Clostridium botulinum'' and related species. It prevents the release of the neurotransmitter acetylcholine from axon endings at the neuromu ...

M03B Muscle relaxants, centrally acting agents

M03BA
Carbamic acid Carbamic acid, which might also be called aminoformic acid or aminocarboxylic acid, is the chemical compound with the formula . It can be obtained by the reaction of ammonia and carbon dioxide at very low temperatures, which also yields an ...
esters

:M03BA01

Phenprobamate Phenprobamate (Gamaquil, Isotonil) is a centrally acting skeletal muscle relaxant, with additional sedative and anticonvulsant effects. Overdose is similar to barbiturates. Its mechanism of action is probably similar to meprobamate. Phenprobamat ...

:M03BA02

Carisoprodol Carisoprodol, sold under the brand name Soma among others, is a medication used for musculoskeletal pain. Use is only approved for up to three weeks. Effects generally begin within half an hour and last for up to six hours. It is taken orally. ...

:M03BA03

Methocarbamol Methocarbamol, sold under the brand name Robaxin among others, is a medication used for short-term musculoskeletal pain. It may be used together with rest, physical therapy, and pain medication. It is less preferred in low back pain. It has lim ...

:M03BA04 Styramate :M03BA05 Febarbamate :M03BA51 Phenprobamate, combinations excluding psycholeptics :M03BA52 Carisoprodol, combinations excluding psycholeptics :M03BA53 Methocarbamol, combinations excluding psycholeptics :M03BA71 Phenprobamate, combinations with psycholeptics :M03BA72 Carisoprodol, combinations with psycholeptics :M03BA73 Methocarbamol, combinations with psycholeptics :QM03BA99 Combinations

M03BB Oxazol,
thiazine Thiazine is an organic compound containing a ring of four carbon, one nitrogen and one sulfur atom. There are three isomers of thiazine, 1,2-thiazine, 1,3-thiazine, and 1,4-thiazine, which differ by the arrangement of the nitrogen and sulfur ato ...
, and
triazine Triazines are a class of nitrogen-containing heterocycles. The parent molecules' molecular formula is . They exist in three isomeric forms, 1,3,5-triazines being common. Structure The triazines have planar six-membered benzene-like ring but ...
derivatives

:M03BB02 Chlormezanone :M03BB03 Chlorzoxazone :M03BB52 Chlormezanone, combinations excluding psycholeptics :M03BB53 Chlorzoxazone, combinations excluding psycholeptics :M03BB72 Chlormezanone, combinations with psycholeptics :M03BB73 Chlorzoxazone, combinations with psycholeptics

M03BC
Ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again b ...
s, chemically close to
antihistamine Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provide ...
s

:M03BC01

Orphenadrine Orphenadrine (sold under many brand names) is an anticholinergic drug of the ethanolamine antihistamine class; it is closely related to diphenhydramine. It is a muscle relaxant that is used to treat muscle pain and to help with motor control in P ...

(citrate) :M03BC51 Orphenadrine, combinations

M03BX Other centrally acting agents

:M03BX01

Baclofen Baclofen, sold under the brand name Lioresal among others, is a medication used to treat muscle spasticity such as from a spinal cord injury or multiple sclerosis. It may also be used for hiccups and muscle spasms near the end of life. It is ...

:M03BX02

Tizanidine Tizanidine, sold under the brand name Zanaflex among others, is a medication that is used to treat muscle spasticity due to spinal cord injury or multiple sclerosis as well as spastic cerebral palsy. Effectiveness appears similar to baclofe ...

:M03BX03 Pridinol :M03BX04 Tolperisone :M03BX05

Thiocolchicoside Thiocolchicoside (Muscoril, Myoril, Neoflax) is a muscle relaxant with anti-inflammatory and analgesic effects. How it works is unknown, but it is believed to be via antagonism of nicotinic acetylcholine receptors. However, it is also appears to ...

:M03BX06

Mephenesin Mephenesin (INN) is a centrally acting muscle relaxant. It can be used as an antidote for strychnine poisoning. Mephenesin however presents with the major drawbacks of having a short duration of action and a much greater effect on the spinal cord ...

:M03BX07 Tetrazepam :M03BX08

Cyclobenzaprine Cyclobenzaprine (sold under the brand name Flexeril, among others) is a medication used for muscle spasms from musculoskeletal conditions of sudden onset. It is not useful in cerebral palsy. It is taken by mouth. Use is not recommended for mo ...

:M03BX09 Eperisone :M03BX30

Phenyramidol Fenyramidol (International Nonproprietary Name, INN) or phenyramidol (British Approved Name, BAN, United States Adopted Name, USAN), trade name Cabral, is a pharmaceutical drug which acts as a muscle relaxant. Drug Interactions Fenyramidol inh ...

:M03BX53 Pridinol, combinations :M03BX55 Thiocolchicoside, combinations :QM03BX90

Guaifenesin Guaifenesin, also known as glyceryl guaiacolate, is an expectorant medication that aids in the elimination of sputum from the respiratory tract. Chemically it is an ether of guaiacol and glycerine. It is often used in combination with other m ...

M03C Muscle relaxants, directly acting agents

M03CA
Dantrolene Dantrolene sodium, sold under the brand name Dantrium among others, is a postsynaptic muscle relaxant that lessens excitation-contraction coupling in muscle cells. It achieves this by inhibiting Ca2+ ions release from sarcoplasmic reticulum ...
and derivatives

:M03CA01

Dantrolene Dantrolene sodium, sold under the brand name Dantrium among others, is a postsynaptic muscle relaxant that lessens excitation-contraction coupling in muscle cells. It achieves this by inhibiting Ca2+ ions release from sarcoplasmic reticulum ...

References

{{Muscle relaxants M03

M03AA Curare Curare ( /kʊˈrɑːri/ or /kjʊˈrɑːri/; ''koo-rah-ree'' or ''kyoo-rah-ree'') is a common name for various alkaloid arrow poisons originating from plant extracts. Used as a paralyzing agent by indigenous peoples in Central and Sout ... alkaloids

M03AB Choline Choline is an essential nutrient for humans and many other animals. Choline occurs as a cation that forms various salts (X− in the depicted formula is an undefined counteranion). Humans are capable of some ''de novo synthesis'' of choline but ... derivatives

M03AC Other quaternary ammonium compounds In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium ca ...