Muscle spasms and pain

The exact mode of action of diazepam (Valium), an antianxiety drug (see Chap. 30), in die relief of painful musculoskeletal conditions is unknown. The drug does have a sedative action, which may account for some of its ability to relieve muscle spasm and pain. 

Benzodiazepines have the capacity to depress polysynaptic reflexes and have been shown to decrease decerebrate rigidity in cats and spasticity in patients with cerebral palsy. What is not clear is whether they can, in humans, relax voluntary muscles in doses that do not cause considerable central nervous system depression. Nevertheless, benzodiazepines, such as diazepam, are often prescribed for patients who have muscle spasms and pain as a result of injury. In these circumstances, the sedative and anxiolytic properties of the drug also may promote relaxation and relieve tension associated with the condition. 

Mechanism of Action A centrally-acting skeletal muscle relaxant whose exact mechanism is unknown. Effects may be due to its CNS depressant actions. Therapeutic Effect Relieves muscle spasms and pain. 

A 50-year-old man with hereditary osteo-onychodys-plasia had smoked marijuana since 1974 to alleviate muscle spasms and pain (current use 7 g/day of 3.75% THC). He had mild-to-moderate impairment of attention and concentration and reduced ability to acquire new verbal material. He scored poorly on the California Verbal Learning Test (CVLT), a measure of short-term memory recall, and had difficulty with motor tasks. 

Muscle spasms and pain are associated with traumatic injuries and many chronic debilitating disorders such as multiple sclerosis. Spasms are caused by hyperex-citable neurons stimulated by cerebral neurons or from lack of inhibition of the stimulus in the spinal cord or at the skeletal muscles. 

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. 

Muscle spasm. The pain induced by muscle spasm results partially from the direct effect of tissue distortion on mechanical nociceptors. Muscle spasm also causes tissue ischemia. The increased muscle tension compresses blood vessels and decreases blood flow. Furthermore, the increased rate of metabolism associated with the spasm exacerbates the ischemia. As discussed earlier, ischemia leads to stimulation of polymodal nociceptors. 

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

Infliximab intravenous infusions result in acute adverse infusion reactions in up to 10% of patients, but discontinuation of the infusion for severe reactions is required in less than 2%. Infusion reactions are more common with the second or subsequent infusions than with the first. Early mild reactions include fever, headache, dizziness, urticaria, or mild cardiopulmonary symptoms that include chest pain, dyspnea, or hemodynamic instability. Reactions to subsequent infusions may be reduced with prophylactic administration of acetaminophen, diphenhydramine, or corticosteroids. Severe acute reactions include significant hypotension, shortness of breath, muscle spasms, and chest discomfort such reactions may require treatment with oxygen, epinephrine, and corticosteroids. 

Although chemonucleolysis has been used for more than 25 years as an alternative treatment for sciatica, there has always been controversy as to its use, and to date many physicians ore still reluctant to use it. Because or the controversial results, it seems desirable to take a closer look at this important feature. In the first clinical series of 75 patients published, 75% good results were reported, although 39% of patients had severe muscle spasms and an increase in back pain for a few days r92], This phenomenon was also reported by others. In recent clinical trials (properly controlled, double-blind prospective studies), an overall success rate of about 70 85% has been reported [93-95J. 

Nausea and vomiting, cramp-like pains low in the abdomen, diarrhea, itching and tingling of the skin, weak pulse, heart pains, shortness of breath, muscle spasms and possibly convulsions, and coma before death... 

Treatment of Uveitis. Atropine is extremely useful in the treatment of anterior uveal inflammation. Atropine relieves the pain associated with the inflammatory process by relaxing the ciliary muscle spasm and helps prevent posterior synechiae by dilating the pupil. 

For their actions on the gut, against muscle spasm and hypermotility, e.g. against colic (pain due to spasm of smooth muscle) and to reduce morphine-induced smooth muscle spasm when the analgesic is used against acute colic. 

For muscle spasms and other painful musculoskeletal disorders. Available in compound form with aspirin and aspirin with codeine. 

Willow bark, which is an anodyne (painkiller), may help mild headache pain but doesn t address the underlying constitutional issues. Kava, an antianxiety agent and antispasmodic, is useful for muscle spasms and anxiety-driven head pain but is ineffective for sinus headaches. Feverfew, a bitter anti-inflammatory, helps vasodilative migraines but does little for vasoconstrictive headaches or those caused by TMJ dysfunction. 

A patient has been receiving abdominal radiotherapy for a period of time for the treatment of colon cancer. She has suffered quite serious nausea as a result of the treatment. You have supplied metoclopramide (in 28 packs of 10 mg tablets) to the patient on a regular basis under PGDs. The patient is now complaining that this drug does not seem to work any more. She has also been experiencing facial muscle spasms and wonders if this could be a side effect of her radiotherapy or the drug. In addition, the patient has developed a painful skin rash over the treatment area. 

This combination is used in addition to rest, physical therapy, and other measures for the relief of pain, muscle spasm, and limited mobility associated with acute, painful musculoskeletal conditions. 

Certain chronic diseases of the CNS (eg, cerebral palsy, multiple sclerosis, stroke) are associated with abnormally high reflex activity in the neuronal pathways that control skeletal muscle the result is painful spasm. Bladder and anal sphincter control are also affected in most cases and may require autonomic drugs for management. In other circumstances, acute injury or inflammation of muscle leads to spasm and pain. Such temporaiy spasm can sometimes be reduced with appropriate drug therapy. 

As stated earlier they are used to relieve painful muscle spasms and spasticity. They relax the muscle without impairing respiration centrally. They have sedative effects. Some have predominantly tranquilizing effect and are classified as such. 

Currently there is renewed interest in the therapeutic potential of cannabinoids as antitussives (Chung 2005). Non-selective cannabinoids have been shown to have wide therapeutic applications for a number of important medical conditions, including pain, anxiety, glaucoma, nausea, emesis, muscle spasms and wasting diseases however, associated side effects such as sedation, cogifitive dysfunction, tachycardia and psychotropic effects have hampered the use of these compounds in the clinic (Porter and Felder 2001). 

Cyclobenzaprine is a central-acting muscle relaxant that is commonly used to treat pain from injury, muscle spasms, and other painful musculoskeletal conditions. It is structurally related to first-generation tricyclic antidepressants such as imipramine and amitriptyline and appears to inhibit the uptake of norepinephrine in the locus coeruleus. Tricyclic compounds with norepinephrine reuptake-inhibiting properties have been shown to exert analgesic effects in chronic nerve and muscle pain by acting primarily within the central nervous system at brainstem as opposed to spinal cord levels, although their action on the latter may contribute to their overall skeletal muscle relaxant activity. The exact mechanism of action of cyclobenzaprine is unknown. 

Metaxalone, like any other muscle relaxants, should be prescribed for regular usage only in the acute phase of persistent musculoskeletal spasm and pain. Metaxalone maybe considered in a case of acute flare-up in patients with chronic musculoskeletal pain. 

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... 

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