Question 1

A patient has localized muscle spasms after an injury. The prescriber has ordered tizanidine [Zanaflex] to alleviate the spasms. When obtaining the patient's health history, the nurse should be concerned about which possible reason for considering another drug?

Accepted Answer

Hepatotoxicity is a serious potential problem in a patient receiving tizanidine, because the drug can cause liver damage. Baseline liver enzymes should be obtained before dosing and periodically thereafter. Analgesic anti-inflammatory drugs commonly are used in conjunction with centrally acting muscle relaxants, so using aspirin is not a concern. This drug does not contribute to malignant hyperthermia. Patients should be advised to avoid alcohol when taking this drug, but a history of occasional alcohol use is not a contraindication.

Question 2

Which drugs are used to treat spasticity?

Accepted Answer

Three drugs-baclofen, dantrolene, and diazepam-are used to treat spasticity. Baclofen and diazepam act in the CNS, whereas dantrolene acts directly on skeletal muscles. With the exception of diazepam, drugs used for muscle spasm, such as metaxalone and tizanidine, are not effective for treating spasticity.

Question 3

Which patient should receive dantrolene [Dantrium] with caution?

Accepted Answer

Dose-related liver damage is the most serious adverse effect of dantrolene and is most common in women older than 35 years. Dantrolene is used to treat spasticity associated with multiple sclerosis, cerebral palsy, and spinal cord injury, so all of these patients would be candidates for this agent. Dantrolene also is used to treat malignant hyperthermia.

Question 4

A nurse is caring for a patient receiving intrathecal baclofen [Lioresal]. The patient is unresponsive. After asking a coworker to contact the provider, the nurse anticipates performing which intervention?

Accepted Answer

An overdose of baclofen can produce coma and respiratory depression, so the nurse would be correct to suspect overdose in this patient. Respiratory support is essential to prevent a fatal outcome. There is no antidote for baclofen overdose. Diazepam would not be indicated, because seizures are not a result of baclofen overdose and may further depress respirations. An electrocardiogram is not indicated for this patient.

Question 5

A nurse is admitting a patient to the hospital. The patient reports taking oral baclofen [Lioresal] but stopped taking the drug the day before admission. The nurse would be correct to anticipate which adverse effects?

Accepted Answer

Abrupt discontinuation of baclofen is associated with visual hallucinations, paranoid ideation, and seizures. Central nervous system effects of baclofen include weakness, dizziness, fatigue, and drowsiness. Respiratory depression is a result of overdose of baclofen.

Question 6

A patient who has a lower back injury exhibits muscle spasms. The provider orders cyclobenzaprine [Flexeril] 10 mg 3 times a day. What will the nurse include when teaching this patient about this drug?

Accepted Answer

Cyclobenzaprine has significant anticholinergic effects and patients should be warned about dry mouth, blurred vision, and constipation. Tizanidine can cause hallucinations and psychotic symptoms. Methocarbamol may turn urine brown, black, or green, which is a harmless side effect. Tizanidine and metaxalone can cause liver toxicity and require monitoring.

Question 7

A patient with cerebral palsy has severe muscle spasticity and muscle weakness. The patient is unable to take anything by mouth. The nurse is correct to anticipate that which medication will be ordered for home therapy?

Accepted Answer

Baclofen is used to treat muscle spasticity associated with multiple sclerosis, spinal cord injury, and cerebral palsy. It does not reduce muscle strength, so it will not exacerbate this patient's muscle weakness. It can be given intrathecally, via an implantable pump, and therefore is a good choice for patients who cannot take medications by mouth. Dantrolene must be given by mouth or intravenously and so would not be a good option for this patient. It also causes muscle weakness. Diazepam is not the first-line drug of choice. Alternative routes to PO administration are IM, IV, or by rectum. Metaxalone is used to treat localized muscle spasms caused by injury and is not used for cerebral palsy.

Question 8

A patient with cerebral palsy who has been receiving baclofen [Lioresal] via gastrostomy tube for 3 months is admitted to the hospital for evaluation of new-onset seizures. What may the nurse suspect to be the cause of these seizures?

Accepted Answer

Baclofen does not appear to cause physical dependence, but abrupt discontinuation has been associated with adverse reactions. Abrupt withdrawal of oral baclofen can cause visual hallucinations, paranoid ideation, and seizures and should be considered when a patient develops these symptoms. Seizures are not a symptom of baclofen toxicity.

Question 9

A nurse is teaching the parent of a child with spastic quadriplegia about intrathecal baclofen [Lioresal]. Which statement by the parent indicates a need for further teaching?

Accepted Answer

Seizures may occur if oral baclofen is withdrawn abruptly; seizures are not an adverse effect of baclofen. If intrathecal baclofen is stopped abruptly, patients can experience life-threatening effects, so parents should be advised not to stop the drug abruptly. The central nervous system effects of baclofen include drowsiness and lethargy, so these effects are expected. Baclofen does not reduce muscle strength. It can cause constipation and urinary retention, and patients should be advised to contact their provider so that these conditions can be treated.

Question 10

A patient with multiple sclerosis needs pharmacologic treatment for spasticity to begin strengthening exercises to improve walking ability. The nurse anticipates that which medication will be ordered for spasticity?

Accepted Answer

Baclofen is used to treat spasms associated with multiple sclerosis. It has no direct muscle relaxant effects, so it does not reduce muscle strength. Dantrolene works well to reduce spasms, but it also has significant effects on muscle strength. Diazepam is not the first-line drug of choice, but it could be used because it does not reduce muscle strength. Metaxalone is not indicated to treat spasms caused by multiple sclerosis.

Quiz 25: Drugs for Muscle Spasm and Spasticity