Muscle Spasms/Spasticity

Question 1

Two groups of drugs that cause skeletal muscle relaxation:

Answer 1

One group for localized muscle spasm

Other group for spasticity.

Question 2

Localized muscle spasm

Answer 2

Cyclobenzaprine (Flexeril)
Tizanadine (Zanaflex)
Diazepam (Valium)

Metaxalone (Skelaxin)
Methocarbamol (Robaxin)
Orphendrine (Norflex)

Carisoprodol (Soma- Schedule IV)

Question 3

Spasticity

Answer 3

Baclofen (Lioresal)
Dantrolene (Dantrium)
Tizanadine (Zanaflex)
Diazepam (Valium)

Question 4

Cyclobenzaprine (Flexeril)

Answer 4

Localized muscle spasm

Category B

Question 5

Tizanadine (Zanaflex)

Answer 5

Localized muscle spasm
AND
Spasticity
Can cause hepatic damage

Question 6

Diazepam (Valium)

Answer 6

Localized muscle spasm
AND
Spasticity

Question 7

Dantrolene (Dantrium)

Answer 7

Spasticity
Causes peripheral muscle weakness
Acts directly on skeletal muscle

Suppresses the release of calcium from the sarcoplasmic reticulum (SR)
Treats spasticity associated with MS; CP; spinal cord injury

Question 8

Metaxalone (Skelaxin)

Answer 8

Localized muscle spasm

Can cause hepatic damage

Question 9

Methocarbamol (Robaxin)

Answer 9

Localized muscle spasm

Question 10

Orphendrine (Norflex)

Answer 10

Localized muscle spasm

Question 11

Carisoprodol (Soma)

Answer 11

Localized muscle spasm

Question 12

Abstinence syndrome

Answer 12

With chronic high-dose therapy; potentially life-threatening abstinence syndrome with abrupt cessation of muscle relaxants

Question 13

Baclofen (Lioresal)

Answer 13

~GABA
Reduces nerve impulses from the spinal cord to skeletal muscle.

DOC for spasticity
Therapeutic uses: Spasticity associated w/ spinal cord injury (paraplegic or quadriplegic); MS; Trauma

Question 14

Baclofen withdrawal

Answer 14

Sudden increase or return of spasticity or tone, profuse sweating, itching without rash.
Fever, elevated HR, RR, hyper/hypotension; confusion.

Severe withdrawal symptoms include hallucinations, delirium, seizures, rhabdomyolysis, organ failure and even death.

Can use diazepam (Valium) to offset withdrawal symptoms.

Question 15

Dantrolene (Dantrium) ADRs

Answer 15

Malignant hyperthermia
Potentially fatal condition also caused by succinylcholine and general anesthetics

Hepatotoxicity
Muscle weakness
Drowsiness
Diarrhea
Acne-like rash

Question 16

Immunomodulators

Answer 16

All patients (regardless of age) should receive immunomodulators for MS

Interferon beta-1a (Avonex) – IM; (Rebif) - SQ
Interferon beta-1b (Betaseron) - SQ
Glatiramer acetate (Copaxone) - SQ

Question 17

Interferon beta-1a (Avonex)

Answer 17

Immunomodulator

Question 18

Interferon beta-1a (Rebif)

Answer 18

Immunomodulator

Question 19

Interferon beta-1b (Betaseron)

Answer 19

Immunomodulator

Question 20

Glatiramer acetate (Copaxone)

Answer 20

Immunomodulator

Question 21

Interferon Beta (1a and 1b)

Answer 21

Immunomodulator

Inhibits dysfunctional immune responses
Reduces the frequency and severity of MS attacks
Reduces the number and size of lesions
Delays progression of disability

Adverse Effects
Flu-like reactions – diminish over time; can start low & titrate up, and give Tylenol or NSAID
Hepatotoxicity – LFTs baseline, 1 mo later, q3mos/1yr & 6mos/yr
Myelosuppression – CBCs same schedule as LFTs
Injection-site reactions
Depression/ Suicidal Ideation*
Drug interactions – caution with others with bone-marrow suppression & hepatotoxicity

Question 22

ADRs of Interferon Beta (1a and 1b)

Answer 22

Flu-like reactions – diminish over time
Hepatotoxicity
Myelosuppression
Depression/Suicidal Ideation

Question 23

Glatiramer Acetate (Copaxone)

Answer 23

First-line therapy for long-term therapy of relapsing-remitting MS

Protects myelin by inhibiting immune response to myelin basic protein; decreases production of proinflammatory cells; increases production of anti-inflammatory cells

ADRs: Brief but severe chest pain after injection