Chapter 58: Musculoskeletal Medications

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What should you do?

It's the kind of question that can really make you pause, especially in healthcare.

So picture this, cycle benzoprene, a muscle reluctance prescribed for your client.

Seems okay, right?

But then you see they're also taking phenolzine, an MAOI, and suddenly, whoa, alarm bells.

This whole scenario, it's not just hypothetical, it really highlights why understanding medication interactions and safety is just so crucial.

It's the core of what we're diving into today.

Exactly.

And yeah, we promise we'll circle back to this specific case and what that nurse needs to do.

That opening really sets the stage, doesn't it?

The high stakes nature of managing medications.

It shows exactly why exploring these musculoskeletal meds today is so vital.

Absolutely.

So our roadmap for this deep dive is the chapter on musculoskeletal medications from the Saunders Comprehensive Review for the NCLE -XPN Examination, Seventh Ed.

And look, this isn't just about, you know, memorizing a big list of drugs.

Our mission here is to get a real understanding.

How do these meds work?

What do they treat?

And maybe most importantly, what are the safety considerations?

That's key for anyone in health care or even if you're just curious about how these things are managed.

Yeah.

Our goal is really to pull out the essential knowledge.

We're talking skeletal muscle relaxants, anti -gout meds, anti -arthritic drugs, and osteoporosis treatments.

We want to clarify the key concepts, really emphasize the safety stuff, help you navigate it all effectively.

Okay.

So let's jump right into skeletal muscle relaxants then.

When we talk about these, the book points out two main ways they work.

They either act directly, right at the neuromuscular junction, you know, where the nerve meets the muscle, or they work indirectly within the central nervous system, brain and spinal cord.

Exactly.

And we usually categorize them as either centrally acting, so they depress activity in the spinal cord or brain, or peripherally acting.

Dantrolene is the main example there.

Peripherally acting ones, they interfere with calcium release inside the muscle fibers.

That stops the contraction.

Got it.

And where do we actually use these?

What are the clinical situations?

Well, their main job is to prevent or relieve muscle spasms and also manage spasticity.

Tasticity.

Yeah, like from spinal cord injuries or acute musculoskeletal pain.

Also chronic conditions, MS, stroke, which the source calls a brain attack, or cerebral palsy.

Right.

And contraindications, things we need to watch out for.

Oh, definitely.

They're generally not for people with severe liver, renal, or heart disease.

Why is that?

Well, those conditions mess with how the body metabolizes or gets rid of the drug, so it can build up, increasing the risk of side effects.

Makes sense.

And interactions.

This is where it gets tricky, right?

Yes.

Extra vigilant here.

The textbook really warns against using these with other CNS depressants, unless there's a very specific reason and close monitoring.

CNS depressants like?

Things like barbiturates, opioids, alcohol, sedatives, hypnotics, even tricyclic antidepressants.

Combining them can seriously ramp up the sedative effects.

Wow.

Okay.

That's a critical point.

That combines CNS depression.

It can lead to way too much drowsiness, dizziness, even dangerously slow breathing.

Okay.

So let's talk side effects then.

What should we be watching for?

Well, the source list, quite a few.

Dizziness, hypotension, that's the drop in blood pressure.

Right.

Drowsiness, muscle weakness,

dry mouth, some GI upset, photosensitivity, so more sensitive to sunlight,

and even liver toxicity, hepatotoxicity.

Thinking about those, it makes total sense why patient education and good nursing assessment are so incredibly important.

Absolutely.

First step always, a thorough medical history.

Get that detailed list of all current meds.

That helps spot potential contraindications or interactions right away.

Right.

And we need to monitor vital signs, pay close attention to blood pressure, and regularly check for those CNS effects like sedation and dizziness.

And with that dizziness and drowsiness, assessing fall risk must be a priority.

Huge priority.

We also need to monitor the actual muscles and joints involved.

Watch for changes in pain, how well the client can move.

And since the liver and kidneys can be affected, keeping an eye on renal function labs is important too.

And for teaching patients.

Well, telling them to take the meds with food can help with that GI upset.

And it's crucial they report any side effects they notice.

We have to really emphasize avoiding alcohol and other CNS depressants while they're on these meds.

That seems key.

It is.

And of course, tell them, you know, no driving, no operating heavy machinery, nothing that needs them to be fully alert.

Safety first.

And don't forget the liver.

You mentioned hepatal toxicity.

The book specifically highlights monitoring liver function tests.

Okay, let's look at some specific drugs.

Baclofen.

Baclofen.

Okay.

So it acts mainly in the CNS.

Side effects can include drowsiness, dizziness, weakness, fatigue,

sometimes nausea, constipation, urinary retention.

And you've got to be cautious if someone has kidney or liver problems or a history of seizures because it can lower the seizure threshold.

What's interesting is how it's given, not just pills, right?

Right.

Our source mentions it can go directly into the spinal fluid, either through an implanted intrathecable pump or even a direct injection by the provider.

That targeted delivery can sometimes give better relief with fewer side effects systemwide.

That pump thing sounds serious, though.

It is.

And for patients with that pump, it's absolutely critical.

I can't stress this enough.

They must keep their refill appointments.

Why?

What happens?

If that pump runs dry, they go into sudden Baclofen withdrawal, and that can be life -threatening.

Really dangerous.

Okay.

Noted.

Critical point.

What about carisoprotal?

Carisoprotal, main things are take it with food for stomach upset and report any rash or allergic signs right away.

Simple enough.

Chloroxazone.

Chloroxazone.

Monitor for hypersensitivity hives, redness, itching, and maybe angioedema, that swelling under the skin.

Okay.

Also, patients might just feel generally unwell, malaise, and it can turn urine orange or red.

Yeah.

It's usually harmless, but good for them to know so they don't panic.

But importantly, Chloroxazone carries a risk of hepatitis and hepatic necrosis.

Liver function monitoring is crucial.

Got it.

Now, cyclobenzaprine, this brings us right back to our opening scenario.

Exactly.

The textbook is crystal clear.

Absolutely contraindicated if someone's taken an MAOI within the last 14 days or if they have cardiac disorders.

The risk of serious, even life -threatening interactions is just too high.

That is a paramount safety issue.

Definitely.

And cyclobenzaprine also has significant anticholinergic effects.

Think atropine -like.

Yeah.

Meaning caution with urinary retention, angle closure, glaucoma, or increased eye pressure.

And it's only meant for short -term use, like two to three weeks max.

Okay.

Then there's dantrolene.

What's different about this one?

It's mechanism.

It works directly on the skeletal muscles to relieve spasticity.

It doesn't go through the CNS.

Interesting.

Downsides.

The big one, liver damage.

So you absolutely need liver function tests before starting and regularly during treatment.

Other possible effects.

GI bleeding, needing to urinate more often.

Impotence, photosensitivity, rash, muscle weakness.

Patients need sun protection and instructions to report any rash, black, or tarry stools, or yellowing skin or eyes immediately.

That signals liver trouble.

Right.

Diazepam is on the list too.

Used for spasticity, but it works via the CNS.

Doesn't directly affect the muscles.

Sedation is a really common side effect.

Okay.

Methacarbamol.

Methacarbamol.

Key thing.

The injectable form is contraindicated in renal impairment.

Good to know.

If you give it IV too fast, it can cause hypotension, slow heart rate, bradycardia, anaphylaxis, even seizures.

So monitor that IV site very carefully for extravasation leakage into the tissues that can cause thrombophlebitis, tissue damage.

Also it might turn urine brown, black, or green.

Tell patients to report blurred vision, congestion, hives, or rash.

Lots to watch with that one.

Tizanidine and MedTax alone.

Both mentioned as having potential for liver damage.

Again, monitor those liver functions.

Seems like a theme.

And orphanadrine.

Highlighted for significant anticholinergic effects, much like cyclobenzaprine.

So same cautions.

Urinary retention, glaucoma, increased eye pressure.

So the big takeaway for all skeletal muscle relaxants.

Drowsiness.

That potential for drysiness is the overarching safety concern.

Patients just have to be cautious.

Okay, let's shift gears.

Antigout medications.

Right.

Gout.

As many know, it's high uric acid in the blood, forms crystals in the joints, causes that awful painful inflammation.

Exactly.

And the main drugs for managing it.

According to our source, the primary ones are allopurinol, colchicine, probenacid, and sulfenpyrazone.

And how do they work, generally?

Generally, they either cut down the body's production of uric acid, or they help the kidneys get rid of more of it.

The goal is always to prevent or relieve gout attacks and manage that high uric acid level

hyperuricemia.

Gotcha.

But these aren't usually for the acute attack itself, right?

Correct.

For the acute attacks, other drugs are key.

NSAIDs are common for inflammation and pain.

And sometimes glucocorticoids are used to reduce inflammation during those flare -ups too.

And cautions for the main anti -out meds.

Used with caution in people with existing GI, kidney, heart, or liver disease.

Okay.

Side effects.

What might we see?

Common stuff can be headache, nausea, vomiting, diarrhea.

More serious things could include blood dyscrasia, like bone marrow suppression, flushed skin, rash,

also potentially uric acid kidney stones, sore gums, maybe even a metallic taste.

So given those, what are the key nursing interventions?

What do we teach patients?

Monitoring serum uric acid levels is obviously essential to see if the drug's working.

Makes sense.

We also track fluid intake and output.

And really encourage high fluid intake, like two to three liters a day, to help prevent kidney stones.

Good tip.

Regular monitoring of CBC, kidney function, liver function tests is also important.

And lifestyle advice.

Diet plays a big role in gout, doesn't it?

Huge role.

Advise patients to avoid or limit alcohol and caffeine.

Those can increase uric acid.

Stress how important it is to stick to the medication schedule, even when they feel fine, to prevent future attacks.

Dietary changes might be needed too, limiting high purine foods.

Things like wine, some alcohol, organ meats, sardines, salmon, scallops, gravy.

They should take the med with food to reduce stomach irritation.

And always report any side effects right away.

Okay, and here's a really important interaction you mentioned.

Aspirin.

Yes.

Critical point.

Avoid aspirin.

It can actually trigger a gout attack in some people.

Wow.

So what do they take for mild pain?

Acetaminophen is generally the recommended safer bet.

Good to know.

Let's look at specifics.

Allopurinol.

Allopurinol can increase the effects of warfarin, the blood thinner, and oral hyperglycemic for diabetes.

Okay.

Also, advise against large doses of vitamin C could increase kidney stone risk.

Rarely there's a serious hypersensitivity syndrome.

Rash, fever, high xenophil, liver kidney problems.

If that happens, stop the drug immediately.

Notify the provider.

Anything else?

Minimize sun exposure, get annual eye exams because of possible visual changes with long term use.

Okay.

Colchicine.

Use cautiously in older, weaker patients and those with heart, kidney, or GI disease.

If GI symptoms pop up, nausea, vomiting, diarrhea, abdominal pain, stop the colchicine and call the provider.

Got it.

And probenecid.

Can cause mild GI effects, so take it with food.

And again, reinforce that aspirin and salicylates, interfere with how it works.

Acetaminophen is preferred over aspirin.

Okay.

Makes sense.

Let's move on to antiarthritic medications now.

Rheumatoid arthritis or RA.

Right.

Our source explains RA is progressive, autoimmune.

Inflammation hits the joint lining, the synovium first, then can damage cartilage and bone.

Untreated, it leads to major joint destruction, impacts mobility, causes a lot of pain.

So the focus of treatment is?

Early diagnosis and aggressive therapy.

The goal is to preserve joint function, slow down the disease.

Meds fall into a few buckets, NSAIDs, glucocorticoids.

Which you've covered elsewhere.

Exactly.

And then the big category, disease -modifying anti -traumatic drugs or DMARDS.

The book also mentions gold salts.

Briefly.

Less common now, but they were used to reduce joint damage progression.

Problem is toxicity itching, rash, metallic taste, mouth sores, diarrhea.

There's an antidote, dimarcoprol, to help clear the gold if needed.

But let's focus on the DMARDS.

They seem central now.

They really are.

DMARDS are effective at slowing the degenerative fexivari, often second line after NSAIDs, but sometimes first line if it's severe.

Important note.

Some are contraindicated in pregnancy.

Big risk to the fetus.

Common side effects, adverse reactions with DMARDS.

Lots of potential issues.

Injection site reactions are common inflammation, pain, bruising, swelling.

Makes sense if they're injected.

Yep.

Systemically you can see bone marrow suppression, that means higher infection risk.

Also fatigue, headache, nausea, vomiting, flu -like symptoms, allergic responses.

So what are the key nursing interventions and teaching points for someone on a DMARD?

Educate them to watch closely for any sign of infection fever, sore throat, extra fatigue, and report it immediately.

If it's an injection, monitor the site for bad irritation, pain, swelling.

Advise them to check with their provider before getting any live vaccines and try to avoid people with active infections.

And labs.

Absolutely essential.

Regular labs to check neutrophil counts, white blood cell counts, platelet counts, need baseline before starting, and regular checks during therapy to catch that bone marrow suppression early.

Okay, let's run through some specific DMARDS and Akinra.

Common side effects are injection site reactions, itching, redness, rash, pain.

A double momam.

Similar injection site reactions are common, but it's also linked to neurological issues.

Numbness, tingling, dizziness, vision changes, leg weakness.

Hazithioprine.

Immunosuppressive, anti -inflammatory.

Potential toxic effects include hepatitis and blood dyscrasias.

What's an immunosuppressant?

Big concern here is nephrotoxicity kidney damage.

Monitor kidney function closely.

Eat intercept.

You mentioned this connects to a practice question.

Right.

Injection site reactions are common.

There's also a risk of worsening heart failure.

And it's associated with CNS, demyelinating disorders, and blood disorders.

This ties directly to practice question 631.

That question asks what data is most important to collect.

The rationale correctly points to monitoring WBC and platelet counts because of that risk of infection and bone marrow suppression with a tannercept.

Got it.

Hydroxychloroquine sulfate.

Often used, right?

Yes.

Key concern.

Potential for retinal damage with long -term use.

Patients must report any visual disturbances, blurred vision, color changes right away.

Regular eye exams are crucial.

Laflinomyth.

Side effects can include diarrhea, respiratory infections, reversible hair loss, rash, nausea.

Also, it can be toxic to the liver hepatotoxic.

Monitor liver function.

Methotrexate.

Very common deardor.

Very common but carries risks.

Hepatic fibrosis scarring in the liver, bone marrow suppression,

GI ulcers, pneumonitis lung inflammation requires careful monitoring of blood counts and liver function.

Penicillamine.

Can cause bone marrow suppression and has been linked to developing certain autoimmune disorders.

Infliximab.

Given by Fifi.

Can cause infusion reactions, fever, chills, itching, hives, chest pain.

Also hepatotoxic, so monitor liver function.

And lastly, sulfasalicine.

Can cause GI and skin reactions, bone marrow suppression, and hepatitis.

Monitor for all those.

Okay, quite a list.

Let's switch gears one last time.

Medications for osteoporosis.

Right.

Osteoporosis, defined as low bone mass, increased bone fragility, leads to a much higher risk of fractures, especially hip, spine, wrist.

And prevention involves.

Calcium and vitamin D are vital.

They help reduce risk, maximize bone growth when you're young, maintain density later.

The main goal of medication therapy is to cut down fractures by keeping or increasing bone strength.

And the meds fall into two main types.

Correct.

You've got anti -resorptive medications, they slow down bone breakdown.

And then meds that actually promote new bone formation.

Okay, let's start with anti -resorptives.

Salmon calcitonin.

Calcitonin inhibits osteoclasts.

Those are the cells that break down bone, slows bone resorption.

How's it given?

Either as a nasal spray or a subcutaneous injection.

With the nasal spray, check for irritation, alternate nostrils.

Important thing to monitor for is hypocalcemia, low blood calcium.

Okay.

Next up, a big class.

Bisphosphonates,

alendronate, rhizobanate, abandronate.

Yes, these also work by inhibiting those osteoclasts, helping increase bone mass.

But they have some really important contraindications.

Such as?

Shouldn't be used if someone has esophageal problems that hinder swallowing.

Or if they can't sit or stand upright for at least 30 minutes after taking it, it's 60 minutes for ibandronate.

Why that upright requirement?

Risk of esophagitis inflammation of the esophagus.

That's a key adverse effect, along with muscle pain and sometimes eye problems.

Patients need to report those.

And the administration rules are very strict, right?

Ties into another practice question?

Absolutely strict.

Directly ties to practice question 632 about alendronate.

They must be taken first thing in the morning.

Empty stomach.

Before any food or drink, other than plain water, take it with a full glass of water.

And then crucially, stay upright, sitting or standing for at least 30 minutes.

60 for abandronate.

No lying down.

Minimizes that esophageal risk.

Got it.

Very specific.

Riloxapine is another anti -resorptive, but not a bisphosphonate.

Correct.

It's a CIRM -selective estrogen receptor modulator.

Contra indicated if there's a history of venous thromboembolic events, like DBT or PE, also needs to be stopped 72 hours before any long periods of immobilization, like bed rest, long travel because of clot risk.

Advise patients against long stretches of restricted activity, too.

Okay.

Now, the other category.

Promoting bone formation.

Teraparotide.

Teraparotide is unique.

It actually stimulates new bone formation, increases bone mass.

It's a synthetic bit of human parathyroid hormone.

Works by boosting osteoblasts, the bone -building cells.

Who gets this one?

Generally reserved for patients at high risk of fractures.

Important note.

Associated with an increased risk of osteosarcoma bone cancer in animal studies, risk in humans is still under evaluation.

Okay.

Thank you.

Now, let's bring it all home.

Back to that opening scenario.

Cyclobenzeprine prescribed.

Patient is on phenylzine and MAOI.

What does the nurse do?

Okay.

So, as we discussed, cyclobenzeprine plus MAOI within 14 days is for absolute contraindication.

High risk of serious reactions, like hypertensive crisis.

Phenylzine is an MAOI.

So the action is?

The nurse must withhold the cyclobenzeprine, inform the RN or charge nurse, immediately contact the primary healthcare provider about the interaction, question that prescription before giving the med, administering could be disastrous.

Wow.

Really hammers home the importance of checking that med history before giving anything new.

Absolute critical.

Okay.

Let's quickly zip through some of the other practice questions just to reinforce these points.

We covered 631 on a Tannercept monitoring and 632 on a London aid administration.

Question 633.

Common side effect of baclofen.

Drowsiness.

Classic CNS depressant effect.

Dizziness, weakness, fatigue also common, but drowsiness is a big one.

Question 634.

Acceptable responses to DR therapy.

Acceptable things would be better symptom control, normal blood counts, WBC platelets, neutrophils, x -rays showing no further joint damage and increased range of motion over time.

Inflammation at an injection site or a low fever.

Not acceptable might signal problems.

Question 635.

Client on baclofen feels weak, fatigued, wants to stop.

Most appropriate response.

Advise them they must taper the dose gradually with their provider's guidance.

Stopping abruptly can cause serious withdrawal.

Don't just stop it cold.

Question 636.

Most important lab test for dantrolene adverse effect.

Liver function tests.

That dose -related liver damage is the most serious risk.

Monitor before and during.

Question 637.

Pre -existing condition with baclofen prescription that needs a provider call.

History of seizure disorder.

Baclofen can lower the seizure threshold, provider needs to know.

Question 638.

Contraindication for cyclobenzeprine.

History of glaucoma, especially angle closure.

Those anticholinergic effects are the reason.

Can worsen it.

Question 639.

Primary action of dantrolene.

Acts directly on skeletal muscle to relieve spasticity.

Interfers with calcium release in the muscle fiber.

And finally, question 640.

Important discharge instruction for baclofen.

Avoid alcohol.

Both are CNS depressants.

Combining them really potentiates the sedation, dizziness, coordination problems.

Very risky.

The other options aren't standard advice for baclofen.

So to recap this pretty comprehensive exploration today, we really dug into musculoskeletal medications.

Covered skeletal muscle relaxants, antigout meds, antiarthritics, osteoporosis treatments, all based on that Saunders Comprehensive Review chapter.

We hit mechanisms, side effects, those crucial safety points, and key nursing responsibilities.

Hopefully you listening have a much clearer picture now, not just what these drugs are, but the why behind using them safely and effectively.

Yeah, and something maybe to think about further is how interconnected these conditions often are.

You know, inflammation is big in both arthritis and gout.

Mobility issues from spasms or pain can affect bone health down the line, maybe increasing osteoporosis risk.

Interesting point.

So maybe exploring how lifestyle factors, diet, exercise, even stress play into managing these conditions could be a good next step for you.

Or maybe just digging deeper into the pharmacology of a drug that really caught your interest today.

Good thought.

And with that, we can confidently say this deep dive has covered the entire chapter on musculoskeletal medications from the Saunders Comprehensive Review for the NCLE -XPN Examination Seventh Ed,

hopefully giving you a solid foundation in this really important area of pharmacology.