Skeletal muscle spasm

The skeletal muscle relaxants are contraindicated in patients with known hypersensitivity. Baclofen is contraindicated in skeletal muscle spasms caused by rheumatic disorders. Carisoprodol is contraindicated in patients with a known hypersensitivity to meprobamate. Cyclobenzaprine is contraindicated in patients with a recent myocardial infarction, cardiac conduction disorders, and hyperthyroidism, hi addition, cyclobenzaprine is contraindicated within 14 days of the administration of a monoamine oxidase inhibitor. Oral dantrolene is contraindicated in patients with active hepatic disease and muscle spasm caused by rheumatic disorders and during lactation. See Chapter 30 for information on diazepam. 

Muscle relaxant As an adjunct for the relief of skeletal muscle spasm because of reflex spasm caused by local pathology, spasticity caused by uppermotor neuron disorders, athetosis, stiff-man syndrome, used parenterally in the treatment of tetanus (diazepam). 

Oral Treatment of skeletal muscle spasm resulting from rheumatic disorders stroke,... 

Pharmacology Cyclobenzaprine, structurally related to the tricyclic antidepressants (TCAs), relieves skeletal muscle spasm of local origin without interfering with muscle function. It is ineffective in muscle spasm caused by CNS disease. The net effect is a reduction of tonic somatic motor activity, influencing both gamma and alpha motor systems. 

An adjunct for the relief of skeletal muscle spasm caused by reflex spasm to local pathology (such as inflammation of the muscles or joints, or secondary to trauma) spasticity caused by upper motor neuron disorders athetosis stiff-man syndrome. Injectable diazepam may also be used as an adjunct in tetanus. 

Oral Active hepatic disease, such as hepatitis and cirrhosis where spasticity is used to sustain upright posture and balance in locomotion or to obtain or maintain increased function treatment of skeletal muscle spasm resulting from rheumatic disorders. 

Mecfianism of Action A centrally acting skeletal muscle relaxant that reduces tonic somaticmuscleactivityat the level of the brainstem. TfterflpeMtic Effect Relieves local skeletal muscle spasm. 

Uniabeied Uses Treatment of alcohol withdrawal, panic disorders, skeletal muscle spasms, chemotherapy-induced nausea orvomiting, tension headache, tremors adjunctive treatment before endoscopic procedures (diminishes patient recall)... 

It is used in painful skeletal muscle spasm and is used in combination with paracetamol and diclofenac. 

It is indicated in skeletal muscle spasm, in surgery, orthopaedic procedures, neurological diseases and tetanus. 

Skeletal muscle spasms are used to describe the increased tension often seen in skeletal muscle after certain musculoskeletal injuries and inflammation (muscle strains, nerve root impingements, etc.) occur.20,96 This tension is involuntary, so the patient is unable to relax the muscle. Spasms differ from spasticity because spasms typically arise from an orthopedic injury to a musculoskeletal structure or peripheral nerve root rather than an injury to the CNS. Likewise, muscle spasms are often a continuous, tonic contraction of specific muscles rather than the velocity-dependent increase in stretch reflex activity commonly associated with spasticity. The exact reasons for muscle spasms are poorly understood. According to some authorities, muscle spasms occur because a vicious cycle is created when the initial injury causes muscular pain and spasm, which increases afferent nociceptive input to the spinal cord, further exciting the alpha motor neuron to cause more spasms, and so on.61,96 Other experts believe that muscle spasms occur because of a complex protective mechanism, whereby muscular contractions are intended to support an injured vertebral structure or peripheral joint.96 Regardless of the exact reason, tonic contraction of the affected muscle is often quite painful because of the buildup of pain-mediating metabolites (e.g., lactate). 

DRUGS commonly used to treat skeletal muscle spasms ... 

Borenstein DG, Korn S. Efficacy of a low-dose regimen of cyclobenzaprine hydrochloride in acute skeletal muscle spasm results of two placebo-controlled trials. Clin Ther. 2003 25 1056-1073. 

Calcium chloride Skeletal muscle spasms Calcium stabilizes excitable membranes appears to decrease excitability threshold in peripheral nerves and skeletal muscle 2°/o aqueous solution from positive pole ... 

Magnesium sulfate Skeletal muscle spasms myositis Muscle relaxant effect may be caused by decreased excitability of the skeletal muscle membrane and decreased transmission at the neuromuscular junction 2°/o aqueous solution or ointment from positive pole 2°/o ointment... 

Muscular disorders Diazepam is useful in the treatment of skeletal muscle spasms such as occur in muscle strain, and in treating spasticity from degenerative disorders, such as multiple sclerosis and cerebral palsy. 

Cyclobenzaprine is a centrally acting skeletal muscle relaxant that relieves skeletal muscle spasms of local origin without interfering with muscle function by acting within the CNS at the brain stem. Structurally and pharmacologically related to tricyclic antidepressants, cyclobenzaprine is indicated in the relief of muscle spasms associated with acute painful musculoskeletal conditions. 

Diazepam is useful in the short-term therapy of anxiety, and in the relief of skeletal muscle spasm as seen with upper motor neuron disorders (e.g., cerebral palsy, athetosis). It may also be of use in alcohol withdrawal, in the symptomatic relief of acute agitation, tremor, and impending acute delirium tremens. 

Indications Seizure disorders, anticonvulsants, anxiety, tension and insomnia, surgical adjuncts for conscious sedation or amnesia, skeletal muscle spasms or tremors, delirium, schizophrenia as an adjunct, nausea and vomiting induced by chemotherapy, neonatal opiate withdrawal Common drug examples ... 

Major Applications Bird repellents, sunscreen, antimalarial agent, antiviral agent, ° antitumor agent, 11 antiparasitic agent, 11 treattnent of epilepsy, 1 skeletal muscle spasm, 1 drug-coated coronary stent system ... 

Lundeen, J. E. Pharmaceutical composition comprising combination of non-alkaloid and alkaloid-based component for treating skeletal muscle spasm. U.S. Pat. Appl. Publ. US 2006148841, 2006 Chem. Abstr. 2006,145, 110416. 

Chlorzoxazone (Figure 89.3) is said to act primarily at the level of the spinal cord and subcortical areas of the brain where it inhibits multisynaptic reflex arcs involved in producing and maintaining skeletal muscle spasm of varied etiology. Some studies state the mechanism is mediated via calcium-activated potassium channels, whereas other studies state the mechanism is not mediated via potassium channels [6-8]. 

Valtonen. A controlled clinical trial of chlormezanone, orphenadrine, orphenadrine/paracetamol and placebo in the treatment of painful skeletal muscle spasms. 

Methocarbamol is a central-acting muscle relaxant used to treat skeletal muscle spasms and pain related to severe muscle spasm. It is also associated with significant sedative properties. 

Tazanidine is a centrally acting muscle relaxant prescribed for skeletal muscle spasm and associated pain. It is supplied as a white crystalline powder that is slightly soluble in water. Aqueous solubility decreases... 

Central Muscle Relaxants - There appeared during the year an excellent re-view oi the synthetic centrally acting skeletal muscle relaxants which covers the literature through most of 1966 ". As the authors, Donahoe and Kimura, point out, there continues to be a need for effective chemical compounds which relieve painful skeletal muscle spasms without producing muscular weakness or incapacitating sedative or hypnotic effects. Since most of the clinically useful compounds fall within a few structural classes there is a need for more basic studies involving molecular alteration for evaluation as central muscle relaxants. 

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