Eperisone

drugbox
IUPAC_name = 1-(4-ethylphenyl)-2-methyl-3-(1-piperidyl)propan-1-one


CAS_number = 56839-43-1
ATC_prefix =
ATC_suffix =
PubChem = 3236
DrugBank =
C = 17 | H = 25 | N = 1 | O = 1
molecular_weight = 259.387 g/mol
bioavailability =
protein_bound =
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excretion =
pregnancy_AU =
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legal_status = not licensed
routes_of_administration = O

Eperisone (formulated as the eperisone hydrochloride salt) is an antispasmodic drug, sold in Japan, India, the Philippines, Thailand, Malaysia and Bangladesh under the brand name Myonal.

Eperisone acts by relaxing both skeletal muscles and vascular smooth muscles, and demonstrates a variety of effects such as reduction of myotonia, improvement of circulation, and suppression of the pain reflex. The drug inhibits the vicious cycle of myotonia by decreasing pain, ischaemia, and hypertonia in skeletal muscles, thus alleviating stiffness and spasticity, and facilitating muscle movement cite journal |author=Yang SI, Park HY, Lee SH, "et al" |title=Transdermal eperisone elicits more potent and longer-lasting muscle relaxation than oral eperisone |journal=Pharmacology |volume=71 |issue=3 |pages=150–6 |year=2004 |month=Jul |pmid=15161997 |doi=10.1159/000077449 |url=]

Eperisone also improves dizziness and tinnitus associated with cerebrovascular disorders or cervical spondylosis.

Eperisone has a relatively low incidence of sedation when compared with other anti-spasmodic drugs; this simplifies the clinical application of the drug and makes it an attractive choice for patients who require anti-spasmodic therapy without a reduction in alertness.

Eperisone also facilitates voluntary movement of the upper and lower extremities without reducing muscle power; it is therefore useful during the initial stage of rehabilitation and as a supporting drug during subsequent rehabilitative therapy.

Indications

*Spastic paralysis in conditions such as cerebrovascular disease [http://www.curehunter.com/public/keywordSummaryC030848--4--ethyl-2-methyl-3-piperidino-propiophenone.do]
*spastic spinal paralysis
*cervical spondylosis [cite journal |author=Bose K |title=The efficacy and safety of eperisone in patients with cervical spondylosis: Results of a randomized, double-blind, placebo-controlled trial |journal=Methods Find Exp Clin Pharmacol |volume=21 |issue=3 |pages=209 |year=1999 |doi=10.1358/mf.1999.21.3.534831 |url=http://journals.prous.com/journals/servlet/xmlxsl/pk_journals.xml_summary_pr?p_JournalId=6&p_RefId=534831&p_IsPs=N]
*postoperative sequelae (including from cerebrospinal tumour)http://squarepharma.com.bd/SPL_PI_PDF/myonil226.pdf]
*sequelae to trauma (e.g. spinal trauma or head injury)
*amyotrophic lateral sclerosis
*cerebral palsy
*spinocerebellar degeneration
*spinal vascular diseases and other encephalomyelopathies
*improvement of muscular hypertonic symptoms in conditions such as cervical syndrome, periarthritis of the shoulder, and lumbago [http://www.europeanreview.org/articolo.php?id=502] .

Presentation

Eperisone hydrochloride is available as the brand name preparation Myonal as 50 mg enteric coated tablets, or as 10% granules for oral administration http://di.eisai.co.jp/di/EPI/MYO_T-G_EPI.pdf] . An experimental form of the drug, as a transdermal patch system, has shown promising results in laboratory tests on rodents; however, this product is not currently available for human use.cite journal | author = Yang Sang-In | coauthors = Park Ha-Young, Lee Sang-Ho, Lee Seung-Jin, Han Ok-Yeun, Lim Sung-Cil, Jang Choon-Gon, Lee Wan-Suk, Shin Young-Hee, Kim Jung-Ju, and Lee Seok-Yong | year = 2004 | month = July | title = Transdermal eperisone elicits more potent and longer-lasting muscle relaxation than oral eperisone | journal = Pharmacology | volume = 71 | issue = 3 | pages = 150–6 | doi = 10.1159/000077449 | pmid = 15161997 | accessdate = 2006-18-09] (see Future developments, below).

Dosage and administration

In adults, the usual dose of eperisone is 50-150 mg per day, in divided doses after meals. However, the dosage is adjusted by the prescribing clinician depending on factors such as severity of symptoms, patient age and response.

Eperisone has not been established as definitely safe for paediatric use, therefore its use in paediatrics cannot be recommended without further study .

If elderly patients are treated with eperisone, it is recommended that a reduced dose is used, and the patient closely monitored for signs of psychological hypofunction during treatment .

afety during pregnancy and breast-feeding

Eperisone has not been established to be safe for use by pregnant women; therefore the drug should only be used in pregnant women, or women who may be pregnant, if the expected therapeutic benefits will outweigh the possible risks associated with treatment. The manufacturers of Myonal recommend that the drug is not used during lactation (breast-feeding). If eperisone must be used, it is recommended that the patient stops breast-feeding for the duration of treatment. (It has been reported that Eperisone is excreted in breast milk in an animal study (in rats).

Pharmacology

IUPAC name: (2RS)-1-(4-Ethylphenyl)-2-methyl-3-piperidin-1-ylpropan-1-one monohydrochloride C17H25NO·HCl- mass number= 295.85
* Skeletal muscle relaxation
* Relaxation of hypertonic skeletal muscles
* Improves intramuscular blood flow
* Suppression of spinal reflex potentials
* Reduction of muscle spindle sensitivity via motor neurons
* Vasodilatation and augmentation of blood flow
* Analgesic action and inhibition of the pain reflex in the spinal cord

Contraindications

Eperisone is contraindicated in patients with known hypersensitivity to the drug [ClinicalTrialsGov|NCT00327730|Evaluation of Eperisone HCl in the Treatment of Acute Musculoskeletal Spasm Associated With Low Back Pain] .

Cautions

Eperisone should be administered with care in patients with a history of hypersensitivity to any medication, or with disorders of liver function (Eperisone may aggravate hepatic dysfunction).

Weakness, light-headedness, sleepiness or other symptoms may occur. In the event of such symptoms, the dosage should be reduced or treatment discontinued. Patients should be cautioned against engaging in potentially hazardous activities requiring alertness, such as operating machinery or driving a car .

ide effects

* Shock and Anaphylactoid reactions: In the event of symptoms such as redness, itching, urticaria, oedema of the facecite journal |author=Ueno T, Kawana S |title= [A case of eperisone hydrochloride (myonal)--induced drug eruption leading to erythema and angioedema] |language=Japanese |journal=Arerugi |volume=56 |issue=7 |pages=709–13 |year=2007 |month=Jul |pmid=17671415 |doi= |url=http://jja.jsaweb.jp/2007/056070709e.html] and other parts of the body, dyspnoea etc, treatment should be discontinued and appropriate measues taken.
* Oculo-muco-cutaneous syndrome (Stevens Johnson Syndrome) and Toxic Epidermal Necrolysis: [cite journal |author=Takeshi K, et al |title=Severe Drug Eruption Due to Eperisone Hydrochloride and Fluconazole Supposed to be Accompanied with Viral Infection |journal=Rinsho Derma |volume=46 |issue=7 |pages=995–8 |year=2004 |language=Japanese |url=http://sciencelinks.jp/j-east/article/200423/000020042304A0532555.php] Serious dermatopathy such as oculo-muco-cutaneous syndrome (Stevens-Johnson syndrome) or toxic epidermal necrolysis may occur. Patients should be carefully observed, treatment discontinued and appropriate measures taken, in the event of symptoms such as fever, erythema, blistering, itching, ocular congestion or stomatitis, etc
* Other side effects: anaemia, rash, pruritus, sleepiness, insomnia, headache, nausea ang vomiting, anorexia, abdominal pain, diarrhoea, constipation, urinary retention or incontinence.

Drug interactions

There have been reports of disturbances in ocular accommodation occurring after the concomitant use of tolperisone hydrochloride and methocarbamol.

afety in overdose

Seizures have been reported in an infant after accidental ingestion of eperisone [cite journal |author=Tanno K, Narimatsu E, Takeyama Y, Asai Y |title=Infantile case of seizure induced by intoxication after accidental consumption of eperisone hydrochloride, an antispastic agent |journal=Am J Emerg Med |volume=25 |issue=4 |pages=481–2 |year=2007 |month=May |pmid=17499672 |doi=10.1016/j.ajem.2006.09.002 |url=http://linkinghub.elsevier.com/retrieve/pii/S0735675706003615] .

Future developments

Eperisone suffers from a very low bioavailability when taken orally, as a result of high first pass intestinal metabolism; a transdermal patch containing eperisone is currently in development in South Korea. This has shown promise with antispasmodic effect lasting over 24 hours, compared with 1-2 hours following oral administration.

Eperisone is also under investigation as an anti-hypertensive agent, with promising results from trials on beagles [patent|EP|0310259|Eperisone as a hypotensive agent] .

Notes

References

*cite journal |author=Fujioka M, Kuriyama H |title=Eperisone, an antispastic agent, possesses vasodilating actions on the guinea-pig basilar artery |journal=J. Pharmacol. Exp. Ther. |volume=235 |issue=3 |pages=757–63 |year=1985 |month=Dec |pmid=3935775 |doi= |url=http://jpet.aspetjournals.org/cgi/content/abstract/235/3/757
*cite journal |author=Inoue S, Bian K, Okamura T, Okunishi H, Toda N |title=Mechanisms of action of eperisone on isolated dog saphenous arteries and veins |journal=Jpn. J. Pharmacol. |volume=50 |issue=3 |pages=271–82 |year=1989 |month=Jul |pmid=2761129 |doi= |url=http://joi.jlc.jst.go.jp/JST.Journalarchive/jphs1951/50.271?from=PubMed