Karch's PrepU (Pharm) CH. 25: Muscle Relaxants
A patient has been prescribed methocarbamol for fibromyalgia. The nurse has spent an hour educating the patient on the use of methocarbamol for muscle pain. Which statement by the patient indicates that the patient has an understanding of at least one of the significant side effects of methocarbamol? "My urine could be discolored while I take this drug." "I should have lots of energy while taking this drug." "I will probably have diarrhea while taking this drug." "This drug will help my tension headaches."
"My urine could be discolored while I take this drug." Explanation: One significant side effect of methocarbamol is that it causes urine to be discolored. Central-acting muscle relaxants such as methocarbamol usually cause fatigue and loss of energy along with constipation, not diarrhea. Methocarbamol is not designed to treat tension headaches.
The perioperative nurse is caring for a client who requires an umbilical hernia repair but who has a known family history of malignant hyperthermia. The client has been prescribed dantrolene 2.5 mg/kg IV one hour before surgery. The client weighs 121 lbs. The nurse reconstitutes a single-use vial as per the manufacture's instructions, yielding a solution with a concentration of 50 mg/mL. How many mL of the reconstituted dantrolene solution should the nurse add to the client's bag of intravenous fluid? 2.75 mL 2.5 mL 6.05 mL 6.87 mL
2.75 mL Explanation: The client's weight in kilograms is 55 kg (121 lbs divided by 2.2). The ordered dose is 2.5 mg/kg and 55 kg x 2.5 mg = 137.5 mg. There are 50 mg in each mL of the reconstituted solution. Dividing the dose required (137.5 mg) by the dose available (50 mg/mL) yields 2.75 mL
Which instruction should the nurse specifically stress when administering drugs used for muscle spasm and cramping? Take the drug with food. Stay upright for 30 minutes after taking the drugs. Avoid alcohol or other CNS depressants. Take the drug with 6 to 8 oz of water.
Avoid alcohol or other CNS depressants. Explanation: The nurse should instruct the patient to avoid alcohol or other CNS depressants when taking a drug for muscle spasms and cramping. The nurse should instruct patients taking drugs for osteoporosis to take them with 6 to 8 oz of water and to stay upright for 30 minutes after taking drugs. The nurse should instruct patients with gout to take drugs for treating gout with food.
The client is taking cyclobenzaprine for muscle spasms secondary to an injury to the lumbar spine that occurred while lifting a motor at work. The client is being seen for a follow-up visit by the health care provider. The client reports dry mouth, blurred vision, and constipation. Why is the client having these side effects from cyclobenzaprine? Cyclobenzaprine produces an anticholinergic response Cyclobenzaprine acts in the peripheral nervous system Cyclobenzaprine has an effect at the neuromuscular junction Cyclobenzaprine is structurally similar to amitriptyline
Cyclobenzaprine produces an anticholinergic response Explanation: Cyclobenzaprine relieves muscle spasms through a central action, possibly at the level of the brain stem, with no direct action on the neuromuscular junction or the muscle involved. The common adverse effects of cyclobenzaprine are related to its CNS depression and anticholinergic activity. The most common adverse effects are drowsiness, dizziness, and dry mouth.
A client with amyotrophic lateral sclerosis is experiencing muscle spasticity. Which drug would the nurse expect the physician to order? Chlorzoxazone Metaxalone Dantrolene Methocarbamol
Dantrolene Explanation: Dantrolene is indicated for the control of spasticity resulting from upper motor neuron disorders such as amyotrophic lateral sclerosis. Chlorzoxazone, metaxalone, and methocarbamol are used to treat acute musculoskeletal conditions.
What is the most important teaching from the plan of care, to emphasize, when a client is prescribed a skeletal muscle relaxant? Do not drive or operate machinery until individual drug effects are known. Always take this medication with food to prevent nausea and vomiting. Report increased muscle spasm to the health care provider immediately. Drink eight to 10 glasses of water daily to prevent constipation.
Do not drive or operate machinery until individual drug effects are known. Explanation: Drowsiness is the most common reaction seen with the use of skeletal muscle relaxants. The priority of care is safety; therefore, the most important teaching is to tell the client not to drive or operate machinery until the client knows how the drug affects him/her individually. Nausea and constipation may occur, but are not safety priorities. Increased muscle spasm may indicate the drug is not effective, but is not a high safety concern.
The nurse is caring for a client who is receiving cyclobenzaprine for relief of muscle spasms. What adverse effect should the nurse assess for? Muscle spasms Insomnia Drowsiness Urinary incontinence
Drowsiness Explanation: A common adverse effect with cyclobenzaprine is drowsiness. The client will not experience muscle spasms, insomnia, or urinary incontinence as a result of this medication therapy.
The nurse is providing education to a client who has been prescribed dantrolene. What serious adverse effect should the nurse mention during teaching? Metabolic acidosis Hypercarbia Renal calculi Hepatitis
Hepatitis Explanation: The most serious adverse effect of oral dantrolene is fatal hepatitis. Metabolic acidosis, hypercarbia, and renal calculi are not adverse effects of oral dantrolene.
When does a client with spinal cord injury-associated spasticity require treatment for this condition? Ambulation is possible only with an assistive device. Safety, mobility, and activities of daily living are impaired. Pain is present in all affected extremities. Orthopedic procedures are indicated.
Safety, mobility, and activities of daily living are impaired. Explanation: In clients with spinal cord injury, spasticity requires treatment when it impairs safety, mobility, and the ability to perform activities of daily living (e.g., self-care in hygiene, eating, dressing, and work or recreational activities). The treatment should be implemented before the other options occur.
Centrally acting skeletal muscle relaxants lyse or destroy the spasm. True False
True Explanation: The centrally acting skeletal muscle relaxants work in the CNS to interfere with the reflexes that are causing the muscle spasm. Because these drugs lyse or destroy spasm, they are often referred to as spasmolytics.
A client with muscle spasticity has been prescribed baclofen. In order to promote the safe use of this medication, the nurse should encourage the client to: avoid drinking alcohol for the duration of treatment. avoid eating grapefruit or drinking grapefruit juice until treatment is discontinued. increase intake of foods that are high in potassium. increase fluid intake and self-monitor for decreased urine output.
avoid drinking alcohol for the duration of treatment. Explanation: The CNS depressant effects of baclofen can be dangerously exacerbated by alcohol, which should be avoided. Grapefruit is not contraindicated and there is no reason to increase potassium or fluid intake while taking baclofen.
A client with a lower back injury was recently prescribed chlorzoxazone 250 mg PO t.i.d. The client has phoned the clinic, telling the nurse, "My pain's better, but I'm worried that my bladder is bleeding because there's been blood in my urine." What is the nurse's best response" "This drug causes your urine to change color, so it's not likely blood that you're seeing." "It's likely that your chlorzoxazone is reacting with one of your other medications." "There's a risk of that with this particular medication, so you should come be assessed promptly." "Please check in again if it doesn't clear up within the next 24 hours."
"This drug causes your urine to change color, so it's not likely blood that you're seeing." Explanation: Chlorzoxazone causes discoloration of the urine that can mimic hematuria. This is not due to a drug-drug interaction. Telling the client to monitor this for the next day without giving any explanation will not alleviate the client's concern.
A client with a lower back injury was recently prescribed chlorzoxazone 250 mg PO t.i.d. The client has phoned the clinic, telling the nurse, "My pain's better, but I'm worried that my bladder is bleeding because there's been blood in my urine." What is the nurse's best response" "This drug causes your urine to change color, so it's not likely blood that you're seeing." "It's likely that your chlorzoxazone is reacting with one of your other medications." "There's a risk of that with this particular medication, so you should come be assessed promptly." "Please check in again if it doesn't clear up within the next 24 hours."
"This drug causes your urine to change color, so it's not likely blood that you're seeing." Explanation: Chlorzoxazone causes discoloration of the urine that can mimic hematuria. This is not due to a drug-drug interaction. Telling the client to monitor this for the next day without giving any explanation will not alleviate the client's concern.
A 1-month-old newborn weighing 11 lb. who was a precipitous birth is diagnosed with tetanus. How many milligrams (mg) of methocarbamol should the client receive intravenously (IV) per day when the prescribed amount is 15 mg/kg? Record your answer using a whole number.
75 Explanation: Methocarbamol is approved as treatment for tetanus in pediatric clients. The client's weight needs to be converted from pounds (lb) to kilograms (kg) by dividing the weight in pounds by 2.2, or 11/2.2 = 5 kg. To determine the dose, multiply the weight by the dose, or 5 kg x 15 mg = 75 mg. The client should receive 75 mg.
The nursing instructor is teaching a group of students about drugs used for muscle spasms and cramping. The instructor determines the session is successful when the students correctly choose which instruction as relevant to skeletal muscle relaxants? Take the drug with food. Stay upright for 30 minutes after taking the drugs. Avoid alcohol or other CNS depressants. Take the drug with 6-8 ounces of water.
Avoid alcohol or other CNS depressants. Explanation: The nurse should instruct the client to avoid alcohol or other CNS depressants when taking a drug for muscle spasms and cramping. The nurse should instruct clients taking drugs for osteoporosis to take them with 6-8 ounces of water and to stay upright for 30 minutes after taking drugs. The nurse should instruct clients with gout to take drugs for treating gout with food.
A client has been admitted to the unit for treatment of a multiple sclerosis exacerbation. The admission order indicates that the client is taking baclofen. Which outcome would the nurse expect to be associated with use of this medication? Reduction in the appearance of new lesions in magnetic resonance imaging (MRI) studies Decreased muscle spasms Increased muscle strength Decreased severity and duration of exacerbations
Decreased muscle spasms Explanation: Baclofen, a GABA agonist, is used in the treatment of spasms. It can be administered orally or by intrathecal injection. Avonex and Betaseron reduce the appearance of new lesions in MRI studies. Corticosteroids limit the severity and duration of exacerbations. Anticholinesterase agents increase muscle strength in the upper extremities
An operating room nurse is assisting the anesthesiologist in the preparation of an intravenous dose of dantrolene. What emergent issue most likely prompted the need to give the patient dantrolene? Cerebrovascular accident Malignant hyperthermia Myocardial ischemia Uncontrolled hypertension
Malignant hyperthermia Explanation: IV dantrolene is the drug of choice, when accompanied by supportive measures, for acute treatment of malignant hyperthermia. The drug is not used in the treatment of emergent CVA, myocardial ischemia, or hypertension.
A 40-year-old client with a diagnosis of fibromyalgia has been prescribed cyclobenzaprine (Flexeril) as an adjunct to her existing drug regimen. What nursing diagnosis should the nurse prioritize for the nursing care plan for this client? Risk for Injury related to CNS depressant effects Diarrhea related to anticholinergic effects Altered Nutrition, Less than Body Requirements, related to appetite suppression Impaired Swallowing related to increased muscle tone
Risk for Injury related to CNS depressant effects Explanation: The CNS depression that is associated with the use of cyclobenzaprine constitutes a risk for injury. The anticholinergic effects of the drug constitute a risk for constipation, not diarrhea. Nutrition and swallowing are not typically affected by the use of cyclobenzaprine.
A history of what medical condition would contraindicate the use of cyclobenzaprine for acute muscle spasms? cardiac arrhythmias diabetes mellitus transient ischemic attacks (TIA) chronic obstructive pulmonary disease (COPD)
cardiac arrhythmias Explanation: Contraindications to cyclobenzaprine include acute myocardial infarction, arrhythmia, heart block, conduction disturbances, heart failure, and hyperthyroidism. The other listed health problems do not contraindicate its use.
While most muscle relaxants drugs are central nervous system (CNS) depressants, which medication acts only on the muscle? tizanidine dantrolene metaxalone carisoprodol
dantrolene Explanation: Dantrolene is the only skeletal muscle relaxant that acts peripherally on the muscle itself; it inhibits the release of calcium in skeletal muscle cells, thereby decreasing the strength of muscle contraction.
Which medication would the nurse expect to administer if prescribed to achieve skeletal muscle relaxation? Baclofen Allopurinol Alendronate Hydroxychloroquine
Baclofen Explanation: Baclofen is an example of a skeletal muscle relaxant. Allopurinol would be administered to treat gout. Alendronate would be administered to treat osteoporosis. Hydroxychloroquine would be used to treat rheumatoid arthritis.
A client with a history of malignant hyperthermia is scheduled for surgery. Which agent would the nurse most likely expect to administer? Botulinum toxin type B Dantrolene Baclofen Methocarbamol
Dantrolene Explanation: Dantrolene is the drug that would be used as prevention and treatment of malignant hyperthermia.
During surgery to repair a ruptured Achilles tendon, the client develops severe muscle contractions and a dramatic rise in body temperature. Which medication will be administered? Dantrolene sodium Baclofen Carisoprodol Cyclobenzaprine
Dantrolene sodium Explanation: The signs indicated in the scenario suggest malignant hyperthermia. Of the choices offered, dantrolene is the only agent used to treat the condition.
An older adult resident of a long-term care facility is experiencing muscle spasticity and has just been prescribed a centrally acting skeletal muscle relaxant. The client has comorbidities of early stage Alzheimer's disease and chronic obstructive pulmonary disease (COPD). What nursing action should the nurse prioritize for adding to the client's care plan? Falls prevention measures Seizure precautions Continuous pulse oximetry Deep breathing and coughing exercises
Falls prevention measures Explanation: The client's combination of CNS depression from the muscle relaxant and an underlying cognitive deficit creates a risk for falls. This combination is not associated with seizures and will not likely exacerbate the client's COPD; respiratory assessments and interventions would not likely need to be amended.
The nurse is providing education to a client who has been prescribed tizanidine. What adverse effect should the nurse mention during teaching? Eczema Hypotension Dark black urine Excessive salivation
Hypotension Explanation: Hypotension is the most significant adverse effect of tizanidine. Dark black urine, excessive salivation, and eczema are not adverse effects of tizanidine.
The nurse is caring for a client whose current medication regimen includes baclofen 60 mg PO daily. What assessment should the nurse prioritize when assessing for therapeutic effects? Inspection for muscle spasticity and range of motion assessment Bilateral assessment of muscle strength Comparison of fine motor and gross motor skills Assessment for seizure activity
Inspection for muscle spasticity and range of motion assessment Explanation: Baclofen is prescribed to treat muscle spasticity and/or acute musculoskeletal discomfort. It is not an anticonvulsant and does not affect fine motor versus gross motor skills. An absence of spasticity may increase muscle strength but this is not the most direct effect of the medication.
An older adult is prescribed a skeletal muscle relaxant for reports of neck pain. What is the top priority of care for the nurse to teach the family? Administer the medication with meals. Monitor the client before ambulating. Instruct on how to assess client's pain level. Give the medication at the same time each day.
Monitor the client before ambulating. Explanation: Safety is the top priority concern, because skeletal muscle relaxants can cause drowsiness. Administering the medication with meals can reduce GI distress but is not the top priority safety concern. Checking the client's pain level is important but not the top priority safety concern. Giving the medication at the same time each day may help the caregivers remember it, but is not the top priority safety concern.
A client with a spinal cord injury is experiencing increasing muscle spasticity and the care team is considering the use of dantrolene. The nurse should identify what possible contraindication to the safe and effective use of this medication? The client has hepatitis C The client is receiving a selective serotonin reuptake inhibitor for depression The client has a sacral pressure ulcer The client's injury took place less than three months ago
The client has hepatitis C Explanation: Dantrolene is associated with possible hepatocellular injury and a concurrent diagnosis of hepatitis C would require great caution, or may contraindicate the use of dantrolene. Pressure ulcers, use of SSRIs and recent injury do not contraindicate its use.
The health care provider orders short-term skeletal muscle relaxants for an 11-year-old client. The nurse is responsible for the family education plan and teaches the parents that the medications should be used only under which condition? When close supervision is available for monitoring drug effects When the spasms cause uncontrolled pain When the client needs to be alert during pain management During school hours to increase alertness and management of spasms
When close supervision is available for monitoring drug effects Explanation: For most of the skeletal muscle relaxants, safety and effectiveness for use in children 12 years of age and younger have not been established. The drugs should be used only when clearly indicated, for short periods, when close supervision is available for monitoring drug effects (especially sedation), and when mobility and alertness are not required.
A surgical client has developed malignant hyperthermia. Which medication can be used to treat this health emergency? metaxalone methocarbamol dantrolene carisoprodol
dantrolene Explanation: Dantrolene acts directly on skeletal muscle to inhibit muscle contraction. It is used to relieve spasticity in neurologic disorders (e.g., MS, spinal cord injury) and to prevent or treat malignant hyperthermia, a rare but life-threatening complication of anesthesia characterized by hypercarbia, metabolic acidosis, skeletal muscle rigidity, fever, and cyanosis. None of the other medications are prescribed for this emergency.
When developing a teaching plan for a client who is to receive carisoprodol, which sign or symptom would the nurse include as a common adverse reaction? Drowsiness Dyspnea Hypertension Tachycardia
Drowsiness Explanation: Drowsiness is the most common adverse reaction to skeletal muscle relaxants like carisoprodol that the nurse should discuss with the client. No correlation is found with skeletal muscle relaxants causing dyspnea. The Disease-modifying antirheumatic medication of leflunomide has the adverse reaction of hypertension. Tachycardia can be seen in the use of skeletal muscle relaxants but is not the most common and is seen in the use of dantrolene and diazepam.
A nurse is caring for a male patient who has a spinal cord injury due to a motorcycle accident. He has been taking dantrolene (Dantrium) for 2 weeks. The nurse will monitor: prothrombin time and partial thromboplastin time. urine specific gravity. alanine aminotransferase and total bilirubin levels. follicle-stimulating hormone levels.
alanine aminotransferase and total bilirubin levels. Explanation: The nurse will monitor alanine aminotransferase and total bilirubin levels, because a serious adverse effect of dantrolene is drug-induced hepatitis. The nurse will also educate the patient and family concerning signs and symptoms of hepatitis. Prothrombin time and partial thromboplastin time would be monitored for someone taking an anticoagulant, not for someone taking dantrolene. Urine specific gravity is part of a urinalysis and would be used to assess urinary function, which is not affected by dantrolene use. Follicle-stimulating hormone level is important to the female reproductive system and would not be assessed in a male.
Dantrolene should be avoided in all patients who are 35 or older because of the increased risk of: congestive heart failure. cerebral hemorrhage. hepatocellular disease. diabetic ketoacidosis.
hepatocellular disease. Explanation: Caution should be used with dantrolene in all patients older than 35 years because of increased risk of potentially fatal hepatocellular disease.
A 32-year-old female client is taking tizanidine (Zanaflex) for spasticity related to her multiple sclerosis. The nurse will inform the client and her husband that the adverse effect that poses the greatest safety risk to the client is: constipation. dry mouth. fatigue. hypotension.
hypotension. Explanation: Tizanidine (Zanaflex) has been associated with hypotension, which could be a safety risk, especially if the client is also taking an antihypertensive drug. Constipation, dry mouth, and fatigue are common adverse effects that do not pose a safety risk.
A 50-year-old woman has begun taking baclofen to treat her recently diagnosed multiple sclerosis (MS). What teaching point should the nurse provide to the patient about her new drug regimen? "It's best to avoid taking a dose of baclofen unless your spasticity becomes impossible to manage." "Make sure that you don't stop taking baclofen suddenly because it might cause your symptoms to rebound quite sharply." "Even though baclofen is a drug that's available over the counter, it still has the potential to cause serious adverse effects if taken incorrectly." "You'll likely have to stop taking your other medications for a week to ten days before starting to take baclofen."
"Make sure that you don't stop taking baclofen suddenly because it might cause your symptoms to rebound quite sharply." Explanation: Abrupt discontinuation of baclofen should be avoided, as it may result in severe side effects such as confusion, seizures, exacerbations of severe spasticity, hallucinations, and other psychiatric disorders. Baclofen is not available over the counter and is prescribed on a scheduled basis, rather than in response to acute symptoms. It is not necessary to stop taking other drugs prior to or during treatment with baclofen.
A client who is experiencing lower back pain has been prescribed cyclobenzaprine. The nurse should provide what health education in order to ensure safe and effective treatment? "This will likely make you drowsy, so don't take it before doing anything that would require alertness." "Don't use this for more than five consecutive days to prevent damage to your liver." "If you experience sedation, seek care promptly since it could be a sign of a serious drug reaction." "Make sure to avoid grapefruit juice and fresh grapefruit until treatment is complete."
"This will likely make you drowsy, so don't take it before doing anything that would require alertness." Explanation: Cyclobenzaprine causes drowsiness because of CNS depression. There is no absolute prohibition against using the drug for more than five days; it is metabolized in the liver but is not noted to be highly hepatotoxic. Sedation is an anticipated adverse effect, not a sign of a serious drug reaction.
A client with multiple sclerosis asks the nurse to explain why deep tissue massages do not relieve spasticity. The nurse should explain that spasticity is caused by: skeletal muscle trauma and will improve in time. nerve damage in the brain and spinal cord, and it is a permanent condition. inflammation of the muscles; therefore, NSAIDs may be effective. stimulation of "association areas" in the brain; therefore, only nerve blocks will be effective.
nerve damage in the brain and spinal cord, and it is a permanent condition. Explanation: Spasticity is caused by nerve damage in the brain and spinal cord. It is a permanent condition that may be painful and disabling.
