central muscle relaxants


Summary: A heterogeneous group of drugs used to produce muscle relaxation, excepting the neuromuscular blocking agents. They have their primary clinical and therapeutic uses in the treatment of muscle spasm and immobility associated with strains, sprains, and injuries of the back and, to a lesser degree, injuries to the neck. They have been used also for the treatment of a variety of clinical conditions that have in common only the presence of skeletal muscle hyperactivity, for example, the muscle spasms that can occur in MULTIPLE SCLEROSIS. (From Smith and Reynard, Textbook of Pharmacology, 1991, p358)

Top Publications

  1. Smith J. Cooling methods used in the treatment of exertional heat illness. Br J Sports Med. 2005;39:503-7; discussion 507 pubmed
    ..There is no evidence to support the use of dantrolene in these patients. Further work should include a randomised trial comparing immersion and evaporative therapy in heatstroke patients. ..
  2. Reulbach U, Dütsch C, Biermann T, Sperling W, Thuerauf N, Kornhuber J, et al. Managing an effective treatment for neuroleptic malignant syndrome. Crit Care. 2007;11:R4 pubmed
    ..The aim of this study was to prove the efficacy of different NMS treatment strategies, focusing on the efficacy of dantrolene...
  3. Hosoya T, Aoyama H, Ikemoto T, Hiramatsu T, Kihara Y, Endo M, et al. [(125)I]-N-[(3-azido-5-iodo)benzyl]dantrolene and [(125)I]-N-[[3-iodo-5-(3-trifluoromethyl-3H-diazirin-3-yl)]benzyl]dantrolene: photoaffinity probes specific for the physiological Ca(2+) release from sarcoplasmic reticulum of skeletal muscle. Bioorg Med Chem Lett. 2002;12:3263-5 pubmed
  4. Orliaguet G, Langeron O, Coirault C, Fratea S, Coriat P, Riou B. Effects of dantrolene on rat diaphragm muscle during postnatal maturation. Anesthesiology. 2001;94:468-74 pubmed
    ..Our study suggests that developmental changes in the pharmacologic response to dantrolene are more rapid than those of ryanodine. ..
  5. Burns A, Meythaler J. Intrathecal baclofen in tetraplegia of spinal origin: efficacy for upper extremity hypertonia. Spinal Cord. 2001;39:413-9 pubmed
    ..Intrathecal baclofen is a safe and effective intervention for treating upper extremity hypertonia of spinal origin. In addition, the level of intrathecal catheter placement is felt to be of importance. ..
  6. Szentesi P, Collet C, Sarkozi S, Szegedi C, Jona I, Jacquemond V, et al. Effects of dantrolene on steps of excitation-contraction coupling in mammalian skeletal muscle fibers. J Gen Physiol. 2001;118:355-75 pubmed
    ..The channel displayed a constant open probability for as long as 30-50 min after the application of the drug. These data locate the binding site for dantrolene to be on the SR membrane, but be distinct from the purified RYR itself. ..
  7. Ikemoto T, Hosoya T, Aoyama H, Kihara Y, Suzuki M, Endo M. Effects of dantrolene and its derivatives on Ca(2+) release from the sarcoplasmic reticulum of mouse skeletal muscle fibres. Br J Pharmacol. 2001;134:729-36 pubmed
    ..8. These results indicate that the difference in opening modes of the RyR-Ca(2+) release channel is recognized by certain Dan derivatives. ..
  8. Nielsen J, Hansen H, Sunde N, Christensen J. Evidence of tolerance to baclofen in treatment of severe spasticity with intrathecal baclofen. Clin Neurol Neurosurg. 2002;104:142-5 pubmed
    ..Complications are often due to infection or catheter problems. ..
  9. Hosoya T, Aoyama H, Ikemoto T, Kihara Y, Hiramatsu T, Endo M, et al. Dantrolene analogues revisited: general synthesis and specific functions capable of discriminating two kinds of Ca2+ release from sarcoplasmic reticulum of mouse skeletal muscle. Bioorg Med Chem. 2003;11:663-73 pubmed

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  1. Wheeler A. Myofascial pain disorders: theory to therapy. Drugs. 2004;64:45-62 pubmed
    ..Chronic myofascial pain is usually a product of both physical and psychosocial influences that complicate convalescence. ..
  2. Denborough M. Malignant hyperthermia. Lancet. 1998;352:1131-6 pubmed
    ..By far the most common is inherited as a mendelian dominant characteristic and at present mutations in the human RYR account for no more than 20% of susceptible families. ..
  3. Nakamura N, Ueda T, Ishikawa R, Tasaka Y, Fukuuchi K, Sato N. Malignant hyperthermia developing during esophageal resection in an 82-year-old man. J Anesth. 2008;22:464-6 pubmed publisher
    ..Because it is necessary to initiate treatment in the early stage of MH, as soon as possible, although MH prevalence is low in the elderly, it is important to suspect MH when hypercapnia and/or hyperthermia are seen. ..
  4. Doherty J, Froom S, Gildersleve C. Pediatric laryngoscopes and intubation aids old and new. Paediatr Anaesth. 2009;19 Suppl 1:30-7 pubmed publisher
  5. Carbajal R, Eble B, Anand K. Premedication for tracheal intubation in neonates: confusion or controversy?. Semin Perinatol. 2007;31:309-17 pubmed
    ..Tracheal intubation without the use of analgesia or sedation should be performed only for urgent resuscitations in the delivery room or other life-threatening situations when intravenous access is unavailable. ..
  6. Bellinger A, Siriwetchadarak R, Rosenquist R, Greenlee J. Prevention of intrathecal baclofen withdrawal syndrome: successful use of a temporary intrathecal catheter. Reg Anesth Pain Med. 2009;34:600-2 pubmed publisher
    ..The ITB infusion was tapered and simultaneously substituted with progressively higher doses of oral antispasmotics. With this strategy, we were able to avoid life-threatening complications. ..
  7. Tscholl P, Junge A, Dvorak J. The use of medication and nutritional supplements during FIFA World Cups 2002 and 2006. Br J Sports Med. 2008;42:725-30 pubmed publisher
    ..The results raise questions as to whether the medication was taken solely for therapeutic reasons. In view of the potential side effects, more restrictive recommendations for sport need to be developed. ..
  8. Quintana L, Lladó A, Butjosa M, Santamaria J, Torras A, Poch E. [Baclofen-associated encephalopathy in a hemodialysis patient with hiccups]. Nefrologia. 2006;26:486-8 pubmed
    ..We present here the case of a hemodialysis patient with intractable hiccups who developed baclofen-associated encephalopathy with this recommended dose. ..
  9. Barroso A, Lima V, Guzzo G, Moraes R, Vasconcellos M, Bezerra M, et al. Efficacy and safety of combined piroxicam, dexamethasone, orphenadrine, and cyanocobalamin treatment in mandibular molar surgery. Braz J Med Biol Res. 2006;39:1241-7 pubmed
  10. Mehvar R, Vuppugalla R. Hepatic disposition of the cytochrome P450 2E1 marker chlorzoxazone and its hydroxylated metabolite in isolated perfused rat livers. J Pharm Sci. 2006;95:1414-24 pubmed
  11. Wu D, Chen X, Ding R, Qiao X, Shi S, Xie Y, et al. Ischemia/reperfusion induce renal tubule apoptosis by inositol 1,4,5-trisphosphate receptor and L-type Ca2+ channel opening. Am J Nephrol. 2008;28:487-99 pubmed publisher
    ..The InsP3R could be a new target for the treatment of renal I/R injury. ..
  12. Salinska E, Sobczuk A, Lazarewicz J. Dantrolene antagonizes the glycineB site of the NMDA receptor. Neurosci Lett. 2008;432:137-40 pubmed publisher
    ..Our results also suggest that the neuroprotective effect of dantrolene may be at least partly explained by its activity as a non-competitive antagonist of NMDA receptors. ..
  13. Hansen C, Gooch J, Such Neibar T. Prolonged, severe intrathecal baclofen withdrawal syndrome: a case report. Arch Phys Med Rehabil. 2007;88:1468-71 pubmed
    ..A potential role for opiates in managing severe baclofen withdrawal is proposed. ..
  14. Park Y, Hay S, King K, Matevosyan K, Poisson J, Powers A, et al. Is it quinine TTP/HUS or quinine TMA? ADAMTS13 levels and implications for therapy. J Clin Apher. 2009;24:115-9 pubmed publisher
    ..The use of plasma exchange in quinine-TMA is called into question. ..
  15. Kramer K, Weber M, Koulousakis A, Lier H, Krep H. [Intrathecal baclofen therapy. Overdose during replacement of a medication pump]. Anaesthesist. 2009;58:891-6 pubmed publisher
    ..The ITB is an increasingly used therapeutic option for multiple sclerosis and cerebral palsy. Therefore, emergency personal and anesthesiologists must be aware of the possible side effects of this medication. ..
  16. Epifano F, Pelucchini C, Curini M, Genovese S. Insights on novel biologically active natural products: 7-isopentenyloxycoumarin. Nat Prod Commun. 2009;4:1755-60 pubmed
    ..The aim of this review is to examine the phytochemical and pharmacological properties of this compound. ..
  17. Hukkanen J, Jacob Iii P, Peng M, Dempsey D, Benowitz N. Effects of nicotine on cytochrome P450 2A6 and 2E1 activities. Br J Clin Pharmacol. 2010;69:152-9 pubmed publisher
    ..CYP2A6 and CYP2E1 activities are not affected by nicotine. The tobacco smoke constituents responsible for the reduced CYP2A6 and increased CYP2E1 activities remain unknown. ..
  18. Sivakumar G, Yap Y, Tsegaye M, Vloeberghs M. Intrathecal baclofen therapy for spasticity of cerebral origin--does the position of the intrathecal catheter matter?. Childs Nerv Syst. 2010;26:1097-102 pubmed publisher
    ..In our series, there was no statistically significant correlation between the position of the intrathecal catheter and the clinical response to the spasticity. ..
  19. Phillips P, Smith S, Kolpin D, Zaugg S, Buxton H, Furlong E, et al. Pharmaceutical formulation facilities as sources of opioids and other pharmaceuticals to wastewater treatment plant effluents. Environ Sci Technol. 2010;44:4910-6 pubmed publisher
    ..These findings suggest that current manufacturing practices at these PFFs can result in pharmaceuticals concentrations from 10 to 1000 times higher than those typically found in WWTP effluents...
  20. Pak S, Jallo G, Biser A, Ziessman H. Indium-111 diethylene-triamine-pentaacetic acid scintigraphy in the evaluation of function and patency of baclofen intrathecal infusion systems. Neurosurg Focus. 2007;23:E17 pubmed
    ..The use of In-111 DTPA scintigraphy of intrathecal baclofen infusion systems can play an important role in determining the functional status of these systems and guiding subsequent patient care. ..
  21. Vorob eva O, Kozlova I. [Comparative effciency of bakloferon and tolperizon central muscle relaxants in complex therapy of back pain]. Voen Med Zh. 2006;327:52-5 pubmed
  22. Dario A, Pisani R, Sangiorgi S, Soragna A, Reguzzoni M, Protasoni M, et al. Baclofen and potential therapeutic use: studies of neuronal survival. Eur J Pharmacol. 2006;550:33-8 pubmed
    ..Considering the above results, we can conclude that at the used concentrations, this drug is safe and its clinical use should be encouraged. ..
  23. Shah J, Wesnes K, Kovelesky R, Henney H. Effects of food on the single-dose pharmacokinetics/pharmacodynamics of tizanidine capsules and tablets in healthy volunteers. Clin Ther. 2006;28:1308-17 pubmed
    ..The large interpatient variability in plasma profiles most likely dampened the ability to fully elucidate the differences between the 2 formulations. ..
  24. Yu J, Song H, Kim B, Park H, Choi K, Kwon Y. Relative bioavailability of generic and branded 250-mg and 500-mg oral chlorphenesin carbamate tablets in healthy Korean volunteers: a single-dose, randomized-sequence, open-label, two-period crossover trial. Clin Ther. 2009;31:2735-43 pubmed publisher
    ..Chlorphenesin carbamate is a skeletal muscle relaxant approved in Korea for use in the treatment of pain and discomfort related to skeletal muscle trauma and inflammation...
  25. Ghoneim E. Electroreduction of the muscle relaxant drug dantrolene sodium at the mercury electrode and its determination in bulk form and pharmaceutical formulation. Chem Pharm Bull (Tokyo). 2007;55:1483-8 pubmed
  26. Gorgey A, Chiodo A, Gater D. Oral baclofen administration in persons with chronic spinal cord injury does not prevent the protective effects of spasticity on body composition and glucose homeostasis. Spinal Cord. 2010;48:160-5 pubmed publisher
    ..The possibility that oral baclofen could exert an independent protective effect needs to be further investigated. ..
  27. Shilt J, Lai L, Cabrera M, Frino J, Smith B. The impact of intrathecal baclofen on the natural history of scoliosis in cerebral palsy. J Pediatr Orthop. 2008;28:684-7 pubmed publisher
    ..The findings suggest that patients receiving ITB experience a natural progression of scoliosis similar to the natural history reported in the literature. Level III. ..
  28. Majumdar A, López Casas J, Poo P, Colomer J, Galvan M, Lingappa L, et al. Syndrome of fixed dystonia in adolescents--short term outcome in 4 cases. Eur J Paediatr Neurol. 2009;13:466-72 pubmed publisher
    ..The condition is allied to CRPS. Treatment with multidisciplinary approach including psychological measures and physiotherapy is more likely to be successful and may prevent unnecessary physical measures. ..
  29. MacIver M. Abused inhalants enhance GABA-mediated synaptic inhibition. Neuropsychopharmacology. 2009;34:2296-304 pubmed publisher
  30. Chandrasekhar S, Cook C, Collard C. Cardiac surgery in the parturient. Anesth Analg. 2009;108:777-85 pubmed publisher
    ..5 L x min(-1) x m(-2) and perfusion pressure >70 mm Hg; 2) maintaining the hematocrit > 28%; 3) using normothermic perfusion when feasible; 4) using pulsatile flow; and 5) using alpha-stat pH management. ..
  31. Kobayashi S, Yano M, Suetomi T, Ono M, Tateishi H, Mochizuki M, et al. Dantrolene, a therapeutic agent for malignant hyperthermia, markedly improves the function of failing cardiomyocytes by stabilizing interdomain interactions within the ryanodine receptor. J Am Coll Cardiol. 2009;53:1993-2005 pubmed publisher
    ..We sought to investigate the effect of dantrolene, a drug generally used to treat malignant hyperthermia, on the Ca2+ release and cardiomyocyte function in failing hearts...
  32. Jensen A, Callesen T, Hagemo J, Hreinsson K, Lund V, Nordmark J. Scandinavian clinical practice guidelines on general anaesthesia for emergency situations. Acta Anaesthesiol Scand. 2010;54:922-50 pubmed publisher
    ..Outside the operation room, rapid sequence intubation is also considered the safest method. For all patients, precautions to avoid aspiration and other complications must also be considered at the end of anaesthesia. ..
  33. Bettelli G. Which muscle relaxants should be used in day surgery and when. Curr Opin Anaesthesiol. 2006;19:600-5 pubmed
    ..Incidence of postoperative residual curarization remains very high. Sugammadex offers new perspectives. ..
  34. Sampat N, Kulkarni R, Sase N, Joshi N, Vora P, Bhattacharya A, et al. Once daily baclofen sustained release or gastro-retentive system are acceptable alternatives to thrice daily baclofen immediate release at same daily dosage in patients. Neurol India. 2009;57:295-9 pubmed publisher
    ..18 +/- 0.92) and GRS (8.14 +/- 1.57 to 5.33 +/- 1.11), suggesting better toleration. Once-daily baclofen SR and GRS are efficacious, convenient, and better-tolerated alternatives to baclofen IR in patients with neurogenic spasticity. ..
  35. Fredheim O, Skurtveit S, Moroz A, Breivik H, Borchgrevink P. Prescription pattern of codeine for non-malignant pain: a pharmacoepidemiological study from the Norwegian Prescription Database. Acta Anaesthesiol Scand. 2009;53:627-33 pubmed publisher
    ..Opioid prescription for pain relief is increasing. Codeine is the dominating opioid in several European countries, with Norway being among the highest codeine users...
  36. Karjalainen M, Neuvonen P, Backman J. Tolfenamic acid is a potent CYP1A2 inhibitor in vitro but does not interact in vivo: correction for protein binding is needed for data interpretation. Eur J Clin Pharmacol. 2007;63:829-36 pubmed
    ..To avoid overestimation of the interaction potential, the inhibitory effect of highly albumin-bound compounds should also be studied in vitro with albumin, or their exact unbound plasma concentration should be used in predictions. ..
  37. Fukuhara T, Tanaka T, Namba Y, Kuyama H. Tangled catheter as a rare cause of baclofen pump malfunction. Surg Neurol. 2009;72:80-2; discussion 82 pubmed publisher
    ..Although the exact mechanism of this complication is unknown, the friction-compression of the catheter against the iliac bone may be the cause. Implanting the pump away from the bony formation may avoid catheter entanglement. ..
  38. Krach L, Kriel R, Nugent A. Complex dosing schedules for continuous intrathecal baclofen infusion. Pediatr Neurol. 2007;37:354-9 pubmed
    ..7; standard deviation, 0.7). Mean total daily dose at chart review was higher in complex dosing (429.3 vs 211.9 microg/day), as was mean follow-up time (4.8 vs 3.9 years). Case examples are presented. ..
  39. Hickey J, Dunnill G, Sansom J. Photoallergic reaction to systemic quinine sulphate. Contact Dermatitis. 2007;57:384-6 pubmed
  40. Weil A, Ruoff G, Nalamachu S, Altman C, Xie F, Taylor D. Efficacy and tolerability of cyclobenzaprine extended release for acute muscle spasm: a pooled analysis. Postgrad Med. 2010;122:158-69 pubmed publisher
    ..8%) and 30 mg (1.6%) than with CIR (7.3%). Once-daily CER was effective in relieving acute muscle spasm based on patient's rating of medication helpfulness at day 4 and was generally well tolerated with a low rate of reported somnolence. ..
  41. Hofer D, Lohberger B, Steinecker B, Schmidt K, Quasthoff S, Schreibmayer W. A comparative study of the action of tolperisone on seven different voltage dependent sodium channel isoforms. Eur J Pharmacol. 2006;538:5-14 pubmed
    ..3), Na(v1.5), and Na(v1.7) isoforms, indicating common structural properties in the local anesthetic receptor site of these three proteins. Interestingly, this characteristic drug action was not observed for tolperisone. ..
  42. Kasatkin D. [Pathogenetic therapy of spasticity]. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108:80-5 pubmed
  43. Diaz Sylvester P, Porta M, Copello J. Halothane modulation of skeletal muscle ryanodine receptors: dependence on Ca2+, Mg2+, and ATP. Am J Physiol Cell Physiol. 2008;294:C1103-12 pubmed publisher
  44. Bae J, Park Y, Sohn U, Myung C, Ryu B, Jang C, et al. HPLC determination of tolperisone in human plasma. Arch Pharm Res. 2006;29:339-42 pubmed
    ..5-1 h), but the mean half-life in Koreans (1.14 +/- 0.27 h) was shorter than that in Europeans (2.56 +/- 0.2 h). The proposed HPLC method is simple, accurate, reproducible and suitable for pharmacokinetic study of tolperisone. ..
  45. Swierczyńska A. [Assessment of spasticity therapy with baclofen pump in children]. Przegl Lek. 2007;64 Suppl 2:15-7 pubmed
    ..In the second group 3 of 5 patients, have started to walk alone or with orthopedic help. Intrathecal baclofen therapy resulted in the good effects in treatment of spasticity in the both groups. ..
  46. Kim H, Kim H, Han E, Park S, Koh J, Kim K, et al. Characterizations of sphingosylphosphorylcholine-induced scratching responses in ICR mice using naltrexon, capsaicin, ketotifen and Y-27632. Eur J Pharmacol. 2008;583:92-6 pubmed publisher
    ..Both the stereospecificity of SPC and the involvement of the Rho/ROCK pathway suggested that SPC-induced scratching is related to the receptor. ..
  47. Roubertie A, Roze E, Bahi Buisson N, Payet C, Echenne B, Doummar D. [Treatment of childhood dystonia]. Arch Pediatr. 2010;17:540-53 pubmed publisher
    ..The rational strategy for therapeutic management of the various types of childhood dystonia is discussed. ..
  48. Burn S, Zeller R, Drake J. Do baclofen pumps influence the development of scoliosis in children?. J Neurosurg Pediatr. 2010;5:195-9 pubmed publisher
    ..A prospective study is recommended to gather further data on the development of scoliosis in this particular population with intrathecal baclofen pumps. ..
  49. Malanga G, Ruoff G, Weil A, Altman C, Xie F, Borenstein D. Cyclobenzaprine ER for muscle spasm associated with low back and neck pain: two randomized, double-blind, placebo-controlled studies of identical design. Curr Med Res Opin. 2009;25:1179-96 pubmed
    ..To evaluate efficacy and tolerability of once-daily cyclobenzaprine extended release (CER) 15- and 30-mg capsules in patients with muscle spasm associated with acute, painful musculoskeletal conditions...
  50. DeJohn P. Be prepared: malignant hyperthermia. OR Manager. 2008;24:26-7, 30 pubmed
  51. Leykin Y, Pellis T, Vincenti E. Highlights in muscle relaxants. Expert Rev Neurother. 2006;6:1833-43 pubmed
    ..However, new neuromuscular blocking agents are marketed on the basis of improvements in the frequency of side effects, safety, reliability, duration, reversibility and undesirable hemodynamic effects. ..
  52. Dan B, Motta F, Vles J, Vloeberghs M, Becher J, Eunson P, et al. Consensus on the appropriate use of intrathecal baclofen (ITB) therapy in paediatric spasticity. Eur J Paediatr Neurol. 2010;14:19-28 pubmed publisher
  53. Jackson J, Anania F. Chlorzoxazone as a cause of acute liver failure requiring liver transplantation. Dig Dis Sci. 2007;52:3389-91 pubmed