An antispasmodic is a pharmaceutical drug or other agent that suppresses muscle spasms.
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 therapeutic groups: neuromuscular blockers and spasmolytics. Neuromuscular blockers act by interfering with transmission at the neuromuscular end plate and have no central nervous system (CNS) activity. They are often used during surgical procedures and in intensive care and emergency medicine to cause temporary paralysis. Spasmolytics, also known as "centrally acting" muscle relaxant, are used to alleviate musculoskeletal pain and spasms and to reduce spasticity in a variety of neurological conditions. While both neuromuscular blockers and spasmolytics are often grouped together as muscle relaxant, the term is commonly used to refer to spasmolytics only.
Colloquially known as "downers", depressants or central depressants are drugs that lower neurotransmission levels, or depress or reduce arousal or stimulation in various areas of the brain. Depressants do not change the mood or mental state of others. Stimulants, or "uppers", increase mental or physical function, hence the opposite drug class from depressants are stimulants, not antidepressants.
Carisoprodol, sold under the brand name Soma among others, is a medication used for musculoskeletal pain. Effects generally begin within half an hour and last for up to six hours. It is taken orally.
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 stores by antagonizing ryanodine receptors. It is the primary drug used for the treatment and prevention of malignant hyperthermia, a rare, life-threatening disorder triggered by general anesthesia or drugs. It is also used in the management of neuroleptic malignant syndrome, muscle spasticity (e.g. after strokes, in paraplegia, cerebral palsy, or patients with multiple sclerosis), and poisoning by 2,4-dinitrophenol or by the related compounds dinoseb and dinoterb.
ATC code M03Muscle relaxants is a therapeutic subgroup of the Anatomical Therapeutic Chemical Classification System, a system of alphanumeric codes developed by the World Health Organization (WHO) for the classification of drugs and other medical products. Subgroup M03 is part of the anatomical group M Musculo-skeletal system.
Guaifenesin, also known as glyceryl guaiacolate, is an expectorant medication taken by mouth and marketed as an aid to eliminate sputum from the respiratory tract. Chemically, it is an ether of guaiacol and glycerine. It may be used in combination with other medications. A 2014 study found that guaifenesin has no effect on sputum production or clearance in upper respiratory infections.
Cyclobenzaprine, sold under several brand names including, historically, Flexeril, is a muscle relaxer used for muscle spasms from musculoskeletal conditions of sudden onset. It is not useful in cerebral palsy. It is taken by mouth.
Meprobamate—marketed as Miltown by Wallace Laboratories and Equanil by Wyeth, among others—is a carbamate derivative used as an anxiolytic drug. It was the best-selling minor tranquilizer for a time, but has largely been replaced by the benzodiazepines due to their wider therapeutic index and lower incidence of serious side effects.
Orphenadrine 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 Parkinson's disease, but has largely been superseded by newer drugs. It is considered a dirty drug due to its multiple mechanisms of action in different pathways. It was discovered and developed in the 1940s.
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 limited use for rheumatoid arthritis and cerebral palsy. Effects generally begin within half an hour. It is taken by mouth or injection into a vein.
Tubocurarine is a toxic benzylisoquinoline 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 mechanical ventilation. Safer alternatives, such as cisatracurium and rocuronium, have largely replaced it as an adjunct for clinical anesthesia and it is now rarely used.
Neuromuscular-blocking drugs, or Neuromuscular blocking agents (NMBAs), block transmission at the neuromuscular junction, causing paralysis of the affected skeletal muscles. This is accomplished via their action on the post-synaptic acetylcholine (Nm) receptors.
Tetrazepam is a benzodiazepine derivative with anticonvulsant, anxiolytic, muscle relaxant and slightly hypnotic properties. It was formerly used mainly in Austria, France, Belgium, Germany and Spain to treat muscle spasm, anxiety disorders such as panic attacks, or more rarely to treat depression, premenstrual syndrome or agoraphobia. Tetrazepam has relatively little sedative effect at low doses while still producing useful muscle relaxation and anxiety relief. The Co-ordination Group for Mutual Recognition and Decentralised Procedures-Human endorsed the Pharmacovigilance Risk Assessment Committee (PRAC) recommendation to suspend the marketing authorisations of tetrazepam-containing medicines across the European Union (EU) in April 2013. The European Commission has confirmed the suspension of the marketing authorisations for Tetrazepam in Europe because of cutaneous toxicity, effective from the 1 August 2013.
Thiocolchicoside is a muscle relaxant with anti-inflammatory and analgesic effects. Its mechanism of action is unknown, but it is believed to be act via antagonism of nicotinic acetylcholine receptors (nAchRs). However, it also appears to be a competitive antagonist of GABAA and glycine receptors. As such, it has powerful convulsant activity and should not be used in seizure-prone individuals.
Mephenoxalone is a muscle relaxant and mild anxiolytic. It inhibits neuron transmission, relaxing skeletal muscles by inhibiting the reflex arc. As the effect of muscle relaxation, mephenoxalone affects mental condition, and is also a treatment for nervousness and anxiety.
Chlorphenesin carbamate is a centrally acting muscle relaxant used to treat muscle pain and spasms. Chlorphenesin carbamate is no longer used for this purpose in most developed nations due to the availability of much safer spasmolytics such as benzodiazepines.
Laudexium metilsulfate is a neuromuscular blocking drug or skeletal muscle relaxant in the category of non-depolarizing neuromuscular-blocking drugs, used adjunctively in surgical anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation.
An analgesic adjuvant is a medication that is typically used for indications other than pain control but provides control of pain (analgesia) in some painful diseases. This is often part of multimodal analgesia, where one of the intentions is to minimize the need for opioids.
Prenderol (Diethylpropanediol) is a simple alkyl diol which has sedative, anticonvulsant and muscle relaxant effects. It is closely related in structure to meprobamate and numerous other alkyl alcohols and diols with generally comparable activity.
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