Skeletal muscle relaxant drugs

Skeletal muscle relaxant. A drug that decreases the tone of voluntary muscles. 

Drowsiness is the most common reaction seen with the use of skeletal muscle relaxants. Additional adverse reactions are given in die Summary Drug Table Drugp Used to Treat Musculoskeletal Disorders. Some of the adverse reactions tiiat may be seen with the administration of diazepam include drowsiness, sedation, sleepiness, letiiargy, constipation or diarrhea, bradycardia or tachycardia, and rash. 

There is an increased central nervous system (CNS) depressant effect when the skeletal muscle relaxants are administered with other CNS depressants, such as alcohol, antihistamines, opiates, and sedatives. There is an additive anticholinergic effect when cyclobenzaprine is administered with other drugs with anticholinergic effects (eg, antihistamines, antidepressants, atropine, haloperidol). See Chapter 30 for information on diazepam. 

SKELETAL MUSCLE RELAXANTS. The nurse gives these drug with food to minimize gastrointestinal distress, hi addition to drug therapy, rest, physical therapy, and other measures may be part of treatment. 

SKELETAL MUSCLE RELAXANTS. These drugs may cause drowsiness. Because of the risk of injury, the nurse evaluates the patient carefully before allowing the patient to ambulate alone. If drowsiness does occur, assistance with ambulatory activities is necessary. If drowsiness is severe, the nurse notifies the primary health care provider before the next dose is due... 

The anesthesiologist selects the anesthetic drug that will produce safe anesthesia, analgesia (absence of pain), and in some surgeries, effective skeletal muscle relaxation. General anesthesia is most commonly achieved when the anesthetic vapors are inhaled or administered intravenously (IV). Volatile liquid anesthetics produce anesthesia when their vapors are inhaled. Volatile liquids are liquids that evaporate on exposure to air. Examples of volatile liquids include halothane, desflurane, and enflurane. Gas anesthetics are combined with oxygen and administered by inhalation. Examples of gas anesthetics are nitrous oxide and cyclopropane. 

Pharmacology In isolated nerve-muscle preparation, dantrolene produced relaxation by affecting contractile response of the skeletal muscle at a site beyond the myoneural junction and directly on the muscle itself. In skeletal muscle, the drug dissociates the excitation-contraction coupling, probably by interfering with the release of calcium from the sarcoplasmic reticulum. 

Geriatric Considerations - Summary Carisoprodol is a skeletal muscle relaxant that at higher doses can cause CNS depression. It appears to have more use with acute muscle discomfort as compared to chronic use. Carisoprodol s metabolite is meprobamate and therefore may have abuse potential and cause sedation in older adults. The risks of fhis drug outweigh benefits in treating older adults. 

Geriatric Considerations-Summary Metaxalone is a skeletal muscle relaxant with a primary effect of general CNS depression. Older adults taking this drug are at risk of somnolence and injuries from falls. 

Skeletal muscle relaxation can be achieved by following group of drugs as in table 2.7.1. 

The physiologic state induced by general anesthetics typically includes analgesia, amnesia, loss of consciousness, inhibition of sensory and autonomic reflexes, and skeletal muscle relaxation. The extent to which any individual anesthetic agent can produce these effects depends on the specific drug, the dosage, and the clinical situation. 

Before the introduction of neuromuscular blocking drugs, profound skeletal muscle relaxation for intracavitary operations could be achieved only by producing levels of volatile (inhaled) anesthesia deep enough to produce profound depressant effects on the cardiovascular and respiratory systems. The adjunctive use of neuromuscular blocking drugs makes it possible to achieve adequate muscle relaxation for all types of surgical procedures without the cardiorespiratory depressant effects produced by deep anesthesia. 

Drug Interactions Antineoplastlc agents Corticosteroids and corticotropin Cyclosporine-A Digitalis glycosides Flucytosine Imidazoles Leukocyte transfusions Nephrotoxic medications Skeletal muscle relaxants Zidovudine... 

There is a very great demand for drugs for the relief of anxiety. This was formerly met by the use of alcohol, bromides or barbiturates, which carried the risk of abuse or dangerous toxicity. The first of the modern minor tranquilizers, introduced from 1946 onwards, were drugs described as skeletal muscle relaxants. These were mainly derivatives of polyhydric alcohols, but heterocyclic examples included metaxolone (161), which is related to the aryl ethers of glycerol, chlorzoxazone (162) and chlormezanone (163). Dantrolene sodium (164) is a muscle relaxant and CNS depressant. 

Chlorzoxazone (Paraflex, Parafon Forte DSC, Others) [Skeletal Muscle Relaxant/ANS Drug] Uses Adjunct to rest physical therapy to relieve discomfort associated w/ acute, painful musculoskeletal conditions Action Centrally acting skeletal muscle relaxant Dose Adults. 250-500 mg PO tid-qid Peds. 20 mg/kg/d in 3-4 + doses Caution [C, ] Avoid EtOH CNS depressants Contra Severe liver Dz Disp Tabs SE Drowsiness, tach, dizziness, hepatotox, angioedema Interactions T Effects W/ antihistamines, CNS depressants, MAOIs, TCAs, opiates, EtOH, watercress EMS Use of CNS depressants and concurrent EtOH use can T sedation urine may turn reddish purple or orange OD May cause N/V/D, dizziness, HA, X deep tendon reflexes, hypotension and resp depression symptomatic and supportive, activated charcoal may be effective... 

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