1. CHAPTER 33 Drugs affecting muscles and joints

2. see box 33-1(pg. 398) for the structure and function of muscles
musculoskeletal disorders produce varying degress of pain and immobility
nervous system disorders often affect muscles
person may need drug therapy to relax muscles
arthritis is a common joint disease, treated with non- steroidal anti-inflammatory (ch. 17) agents and cortico-steroids (ch 28)
gout is a very painful form of arthritis
see box 33-1(pg. 398) for the structure and function of muscles

3. Delegation Guidelines Drugs Affecting Muscles and Joints:
Some drugs affecting muscles and joints are given parenterally- by subcutaneous, intramuscular or intravenous injection. Some are injected into the spinal column. Because you do NOT give such dose forms, they are NOT included in this chapter. Should a nurse delegate the administration of such to you, you must:
- remember that parenteral dosages are often very different from dosages other routes
-Refuse the delegation. Make sure to explain why. Do NOT just ignore the request. Make sure the nurse knows that you cannot give drug and why

4. Centrally Acting Skeletal Muscle Relaxants
used to relieve acute muscle spasm
spasm: involuntary muscle contraction of sudden onset
muscles spasms are often painful
drugs in this class depress the CNS
they do not have a direct effect on muscles or nerve conduction
all drugs in this class cause some degree of sedation
drugs listed in table 33-1 (pg. 400) are used with physical therapy, rest and analgesics
goal of therapy is relief of muscle spasms

5. for centrally acting skeletal muscle relaxants:
Assisting With the Nursing Process
for centrally acting skeletal muscle relaxants:
ASSESSMENT: measure vital signs, observe level of alertness
PLANNING: see table 33-1 for “Adult Dosage”
IMPLEMENTATION: see table 33-1 for “Comments”
EVALUATION: report and record:
sedation, weakness, lethargy, GI complaints: usually mild and resolve, provide for safety
dizziness: provide for safety
sore throat, fever, jaundice, weakness: may signal changes in red blood cells and white blood cells
anorexia, nausea, vomiting, jaundice: may signal liver toxicity

6. Direct-Acting Skeletal Muscle Relaxant:
drug acts directly on skeletal muscle
produces mild weakness of skeletal muscle
decreases the force of reflex muscle contractions, muscle stiffness, involuntary muscle movements and spasticity
it also decreases:
clonus: rapidly alternating involuntary contraction and relaxation of skeletal muscles
hyper-reflexia: increased reflex actions
used to control spasticity of chronic disorders such as cerebral palsy, MS, spinal cord injury, stroke
goal of therapy: relief from muscle spasm
example: dantrolene (Dantrium)

7. dantrolene (Dantrium):
Assisting With the Nursing Process
dantrolene (Dantrium):
ASSESSMENT: measure vital signs, observe muscle spasms that may be present
PLANNING: oral dose forms: 25, 50 and 100mg capsules
IMPLEMENTATION: initial adult dose: 25mg daily, dose increased to 25mg 2-4x/day at 4-7 day intervals. Dosage is gradually increased up to 100mg 2-4x/day. Some persons may require 200mg 4x/day
EVALUATION: report and record:
weakness, diarrhea, drowsiness: usually mild and tend to resolve
dizziness, light-headedness: provide for safety
photo-sensitivity: sensitivity to sunlight and UV light, person should avoid exposure, should apply sunscreen and wear long sleeves, hat, sunglasses when outdoors. sunburn needs medical attention
anorexia, nausea, vomiting, jaundice: may signal liver toxicity

8. Other Muscle Relaxants: baclofen(Lioresal)
used to manage muscle spasticity from MS, spinal cord injury and other spinal cord diseases
goal of therapy: relief of muscle spasm

9. Assisting With the Nursing Process
baclofen (Lioresal)
ASSESSMENT: observe level of alertness
PLANNING: oral dose forms: 10 and 20mg tablets, 10 and 20mg orally disintegrating tablets
IMPLEMENTATION: oral adult dose: 5mg 3x/day. Dosage may be increased by 5mg every 3-7 days based on persons response. Best effects usually occur with dosages of 40-80mg daily. Orally disintegrating tablets provide more rapid onset of action. Used for persons with swallowing problems
EVALUATION: report and record:
nausea, fatigue, headache, drowsiness: usually mild and tend to resolve
dizziness: provide for safety

10. Drugs Used to Treat Gout:
gout occurs when uric acid builds up in body
build-up can lead to kidney stones and sharp uric acid crystal deposits in joints
uric acid comes from breakdown of substances called purines
purines are in all body tissues and some foods
normally uric acid is excreted from body through urine, it can build up in blood when:
body makes too much uric acid
kidneys do not excrete enough uric acid
a person eats too many foods high in purine
first gout attack often happens in big toe
toe is very sore, red, warm and swollen
gout can also occur in: insteps, ankles, heels, knees, wrists, fingers and elbows (fig 33-3)

11. stress, alcohol, drugs and other illnesses can lead to gout
drugs used to treat gout cont…..
signs and symptoms:
pain
swelling
redness
heat
stiff joints
stress, alcohol, drugs and other illnesses can lead to gout
next attack may not occur for months or years
drugs used to treat gout:
NSAIDs (ch. 17)
cortico-steroids (ch. 28)
other agents:
allopurinol (Aloprim and Zyloprim)
Colchicine
Probenecid

12. allopurinol (Aloprim and Zyloprim):
prevents uric acid from forming
goals of therapy:
reduce uric acid blood levels
reduce frequency of acute gout attacks
Assisting With the Nursing Process
allopurinol (Aloprim and Zyloprim)
ASSESSMENT: ask about GI complaints
PLANNING: oral dose forms: 100 and 300mg tablets
IMPLEMENTATION: initial adult dose: 100mg daily, daily dosage is increased by 100mg per week as needed to lower uric acid levels. maximum daily dosage is 800mg. Give drug with food/milk if GI upset occurs
EVALUATION: report and record:
anorexia, nausea, vomiting, jaundice: may signal liver toxicity
sore throat, fever, jaundice, weakness: may signal changes in red blood cells and white blood cells
fever, itching, rash: may signal allergic reaction, tell nurse at once, do NOT give next dose unless approved by nurse

13. Assisting With the Nursing Process
cholchicine
used to prevent or relieve acute gout attack
joint pain/swelling begin to subside within hours after therapy started
goal of therapy: relieve joint pain caused by acute gout attack
Assisting With the Nursing Process
colchicine:
ASSESSMENT: ask about GI complaints, measure intake/output
PLANNING: oral dose forms: 0.5 and 0.6mg tablets
IMPLEMENTATION: initial adult dose: mg. Initial dose if followed by 0.6mg every 1-2 hours until pain subsides or nausea, vomiting and diarrhea develop. Total dose of 4-10mg may be required. To prevent re-current gout dose is mg every 1-3 days. Person should drink oz glasses of fluid daily
EVALUATION: report and record:
nausea, vomiting, diarrhea: drugs are discontinued when these develop
red blood in vomitus, “coffee ground” vomitus, dark tarry stools: signal GI bleeding
sore throat, fever, jaundice, weakness: many signal changes in red blood cells and white blood cells

14. Assisting With the Nursing Process
probenecid
promotes excretion of uric acid through the urine
prevents kidneys from re-absorbing urate
goal of therapy: prevent acute attacks of gouty arthritis
Assisting With the Nursing Process
probenecid:
ASSESSMENT: ask about GI complaints
PLANNING: oral dose forms: 500mg tablets
IMPLEMENTATION: initial adult dose: 250mg 2x/day for 1 week, then increased to 500mg 2x/day. Dosage may be increased by 500mg every few weeks. Maximum daily dose: 2-3g daily. Give drug with food/milk to prevent GI irritation. Person should drink oz glasses of fluid daily
EVALUATION: report and record:
signs/symptoms of acute gout attacks (p. 401)
nausea, anorexia, vomiting: may signal peptic ulcer disease
red blood in vomitus, “coffee ground” vomitus, dark tarry stools: signal GI bleeding
hives, itching, rash: may signal allergic reaction, tell nurse at once, do NOT give next dose unless approved by nurse