Chapter 8: Over-the-Counter Drugs & Natural Health Products

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Welcome to the Deep Dive.

Today we're cutting through the noise,

really getting into something that affects pretty much everyone, over -the -counter meds and natural health products.

Yeah, this is a really important one.

It's less about a single disease state and more about, well, navigating the complexities of Canadian regulation and the safety risks.

These are products people often assume are completely safe.

Exactly, and that assumption is where the danger lies.

So our mission today is to unpack the differences,

prescriptions, OTCs, NHPs, look at the rules governing them in Canada, and really focus on what you need to know clinically for patient safety.

Because if you're dealing with patients, you're dealing with these products.

The goal isn't just definitions, it's understanding the real -world implications.

Okay, let's dive in, maybe start with those definitions just to lay the groundwork.

Sounds good.

So OTC drugs over -the -counter are simply medications you can legally buy without a prescription.

Right, and NHPs, that's the Canadian term, right?

Yes, natural health products.

It's a broad category here in Canada.

Vitamins, herbal remedies, homeopathic stuff, probiotics, all fall under that NHP umbrella.

Got it.

And we should probably contrast that with conventional medicine.

Right, allopathic or western medicine, basically what medical doctors practice.

Okay, and when patients mix these, using alternatives with conventional treatments.

That's what we call complementary medicine.

Often it's referred to as integrative medicine nowadays, and this is really where risk assessment becomes critical.

Okay, so if they're using these things together, how does the Canadian system actually manage access, especially for the OTCs?

Well, it's governed by the Food and Drug Regulations, but the key player for access is the National Drug Scheduling Advisory Committee, NDSAC.

They use the NEPURAI schedules to decide where a drug can be sold.

Ah, the schedules, right, so Schedule 1 is prescription only, pretty straightforward.

Yep, then you have Schedule 2, these are kept behind the counter, restricted access because pharmacist counseling is required before sale.

So things like lower dose codeine preparations or maybe insulin?

Exactly.

Insulin, acetaminophen, with 8 mg of codeine examples like that.

It forces a professional check -in.

That makes sense, it's a built -in safety step.

What about Schedule 3?

Schedule 3 is pharmacy only.

You can find them on the open shelves within the pharmacy, but a pharmacist has to be available if needed.

Think common antihistamines, for example.

Okay, so accessible, but still within the pharmacy environment.

Precisely.

And finally, unscheduled drugs.

These can be sold pretty much anywhere, convenience stores, supermarkets,

ibuprofen, nicotine gum, those sorts of things.

That tiered system really shows they're thinking about different risk levels.

Now what about labeling?

I know there's been a push for clarity.

Yes, the Plain Language Labeling Initiative.

It's a big step.

It requires that standardized drug facts table, much like you see in the U .S.

Right, the one shown in Fig.

8 .1 in the source material.

What does that table mandate?

It makes manufacturers clearly state the purpose, uses, warnings, dosage instructions, potential adverse effects, and crucially, when to consult a provider.

It standardizes the info for consumers.

That seems essential for OTCs, and there's something about a deny number coming too.

Yeah, by 2025, OTCs sold on store shelves will need a drug identification number, a D -ON.

It adds another layer of regulatory oversight and makes tracking easier.

Okay, so the system tries to manage risk, but how does a drug even get to be OTC?

What's the process for switching from prescription?

Ah, that's a really interesting part.

There are specific criteria outlined in Box 8 .1 in the text.

It boils down to three main areas.

Okay, what's the first one?

Indications for use.

Basically, can the average person easily self -diagnose the condition the drug treats, and can they monitor if it's actually working?

Plus, the benefits have to clearly outweigh the risks for self -treatment.

Makes sense.

What's criterion number two?

That's the safety profile.

The drug needs a good track record low rate of serious side effects, limited potential for harmful interactions with other common drugs, and low risk of being misused or abused.

And there's a key term here related to safety.

Yes.

Critically, it needs a high therapeutic index.

Let's just quickly nail that down for everyone.

Therapeutic index.

It's the ratio between the dose that causes toxicity and the dose that provides the therapeutic effect.

A high index means there's a wide margin between an effective dose and a harmful one.

You'd have to take a lot more than recommended to get into serious trouble, accidentally at least.

Got it.

A big safety buffer, ideally.

And the third criterion.

Practicality.

Is the drug easy for a consumer to use correctly?

Is it simple to monitor?

Okay.

So if a drug meets all that, it can potentially move to OTC status.

What are the upsides and downsides of that switch?

Well, the advantages are obvious.

Easier access for self -treatment, potentially lower health care system costs if people don't need a doctor visit just for that medication.

But the downside.

Big ones.

People might delay seeking necessary medical care for a more serious underlying condition.

And costs can actually shift to the patient if their insurance covered the prescription but doesn't cover the OTC version.

Yeah, that out -of -pocket cost is real.

Can you give some examples of drugs that made this switch?

Box 8 .2 mentions a few categories.

Sure.

Common examples include analgesics like ibuprofen and naproxen.

Also, certain histamine blockers used for allergies or heartburn like loratadine or femuradine.

And even some proton pump inhibitors for acid reflux like almorazole.

Okay.

Now, let's talk about the dangers within common OTCs, even if they meet the criteria.

Where are the biggest red flags?

We absolutely have to start with acetaminophen.

Tylenol.

The king of liver toxicity, right?

Absolutely.

It carries a major risk of hepatic toxicity,

serious liver damage, even failure.

The source is crystal clear.

For anyone with normal liver function, the absolute maximum daily dose is 4 ,000 milligrams.

That's 4 grams.

Period.

And the danger is often accidental overdose.

Exactly.

People take acetaminophen for a headache, then they take a cold and flu product that also contains acetaminophen without realizing it.

They stack the drug and easily blow past that 4 ,000 milligram limit.

It's incredibly dangerous.

A crucial point.

What about other common pain relievers, the NSAIDs, ibuprofen, naproxen, aspirin?

They have their own set of risks.

Significant ones, actually.

Gastrointestinal issues like ulcers and bleeding are well known.

But there are also cardiovascular risk, increased chance of heart attack or stroke with some NSAIDs.

Okay.

And cough and cold medicines, especially for kids.

Big warnings there.

Health Canada specifically advises against using most CCMs in children under six.

The risks over sedation, paradoxically excitement or seizures, rapid heart rate, just aren't worth it for the limited benefit in young kids.

And again, the stacking risk with ingredients like acetaminophen or decongestants is high.

And we can't ignore deliberate misuse either, can we?

Pseudoephedrine, the decongestant, is kept behind the counter largely because it's used to illegally make methamphetamine.

And dextromethorphan, the cough suppressant, is unfortunately abused recreationally robo -tripping for its dissociative effects at high doses.

It just shows that even readily available drugs have some serious baggage.

Definitely.

Okay.

Let's pivot slightly now to natural health products or NHPs.

The regulatory side in Canada seems pretty robust on paper, but perception is different.

That's the real challenge with NHPs.

They are regulated in Canada by the Natural and Non -Prescription Health Products Director at the NNHPD.

Products that meet their standards for safety, efficacy and quality get a license and a natural product number, or NPN, on the label.

So that NPN means it's passed some checks.

Yes.

It means Health Canada has assessed it.

But the huge public health issue is this widespread belief.

If it's natural, it must be safe.

Which is just not true.

Not at all.

The scientific concerns are significant.

Often there's limited good quality clinical data, there's potential for allergic reactions, sometimes toxic contaminants, and maybe even mutagenic effects with long -term use of some herbals.

And the biggest risks clinically.

Interactions.

Serious drug interactions.

Patients often don't think to mention NHPs they're taking, or they might even hide it thinking their doctor will disapprove.

This creates a massive safety blind spot.

Okay, let's get specific then.

What are some of the really high alert NHP drug interactions we absolutely need to screen for?

Especially thinking about patients on, say, blood thinners.

Anticoagulants are a huge one.

Several common NHPs increase bleeding risk when taken with drugs like warfarin, or even antiplatelets like aspirin.

Top offenders include gingko belota, chamomile and ginger root.

Using these with blood thinners is a major red flag.

Okay, definite bleed risk there.

What about interactions affecting how the body processes drugs?

Metabolism issues.

The classic example here is grapefruit.

The dreaded grapefruit juice interaction.

Exactly.

It inhibits a key enzyme system in the gut and liver CYP3A4.

This slows down the metabolism of many, many drugs.

So taking those drugs with grapefruit can lead to dangerously high levels in the body.

Which drugs are most affected?

Lots of them.

Certain calcium channel blockers for blood pressure, some statins for cholesterol like atorvastatin or asymvastatin, some psychiatric meds, erectile defunction drugs, and crucially some amino suppressants used after transplants.

The toxicity risk skyrockets.

So a simple breakfast choice could lead to a serious drug overdose effect.

Wow.

What about mood affecting herbals?

St.

John's word is probably the most notorious NHP for interactions.

It has two major issues.

Okay, what's the first one?

It can increase serotonin levels.

If you combine it with prescription antidepressants, especially SSRIs, you risk serotonin syndrome, which can be life -threatening.

Symptoms like confusion, rapid heart rate, sweating,

muscle rigidity.

Very serious.

And the second issue with St.

John's wort.

It's a potent inducer of that same enzyme system we mentioned, CYP3A4 and others.

Okay, grapefruit inhibits it, St.

John's wort induces it.

What does inducing mean in practical terms?

It means it speeds up the metabolism of drugs that use that enzyme pathway.

So it makes the liver break down those other drugs faster.

Which makes them less effective.

Exactly.

It can lower the blood levels of many critical medications, potentially making them useless.

This includes drugs like birth control pills, certain heart medications, HIV protease inhibitors, or for and again, and transplant rejection drugs.

It essentially cancels out their effect.

Like a chemical shredder for other meds?

That's a huge risk.

Any others to quickly mention?

Kava is another one, sometimes used for anxiety.

It can increase the effects of barbiturates and alcohol, leading to excessive sedation.

There have also been concerns about liver toxicity with kava.

Okay, the interaction potential is clearly massive.

Now let's briefly touch on cannabis.

It's legal for recreational use in Canada since 2018, so it's definitely part of this landscape now.

Yes, under the Cannabis Act.

From a pharmacological view, we usually focus on two main cannabinoids, detailed in box

Which are?

Versus THC, that's Delta -9 -tetrahydrocannabinol.

It's the main psychoactive component, the one that causes the high.

It acts on cannabinoid receptors in the brain, affecting pleasure, memory, concentration, etc.

And pharmacokinetically,

how long does it stick around?

That's a key point.

THC has a very long half -life.

It can be 1 .3 days for someone who uses it infrequently, but up to 5 to 13 days for frequent users.

Its effects, and potential interactions, linger much longer than people realize.

Wow, up to almost two weeks for heavy users.

Okay, and the other main component?

That's CBD, or cannabidiol.

It's the major non -psychotropic cannabinoid.

Doesn't cause a high.

But it does have some effects.

Yes, it's noted for having potential anti -epileptic, anti -inflammatory, and anti -anxiety properties.

Is it approved for medical uses?

The clinical trial data is still pretty limited, especially long -term.

But in Canada, specific cannabis -based products are authorized as add -on treatments for things like nerve pain and MS, pain in advanced cancer, AIDS -related appetite loss, and severe nausea from chemotherapy.

But again, patients need to disclose use because it adds to the overall picture of substances they're taking.

Okay, so we've covered OTCs, NHPs, cannabis.

Bringing it all together, what does this mean for day -to -day practice?

Let's talk about the nursing process.

Assessment seems crucial.

It's absolutely paramount.

Because patients often self -medicate and might not volunteer this information, thinking these products are harmless or irrelevant, the medication history has to be incredibly thorough.

More than just asking about prescriptions.

Oh, much more.

You have to explicitly ask about all OTC drugs, all vitamins, all herbals, all NHPs.

And don't forget alcohol, tobacco, caffeine used too.

They all interact.

What else is critical in that assessment phase, beyond just listing products?

You need to assess for allergies, obviously.

But also consider the patient's reading level and cognitive ability.

Can they actually understand the label, directions, and warnings?

Good point.

And underlying health conditions?

Huge factor.

Chronic conditions like diabetes, liver or kidney disease, glaucoma, high blood pressure.

Many OTCs and NHPs are contraindicated or need caution with these conditions.

You have to know the patient's full health picture.

The source material also mentioned an important ethnocultural point.

Yes, that's vital.

It notes, for example, that patients from some cultural backgrounds, like Japanese culture, might be less likely to report subtle side effects, particularly gastrointestinal ones like nausea or changes in bowel habits.

They might see it as complaining or unacceptable.

So you need to be more proactive in asking.

Exactly.

You need to ask specific, open -ended questions about potential side effects, knowing they might not volunteer that information until it's potentially a more serious problem.

Don't just rely on them reporting things spontaneously if their cultural norms discourage it.

Okay, so thorough assessment is step one.

What's the core implementation strategy?

Patient education.

It is absolutely fundamental.

What are the non -negotiable teaching points listeners need to hammer home?

Number one, read labels carefully.

Teach patients to look specifically at the active ingredients.

This is key to avoiding that dangerous stacking we talked about, especially with acetaminophen.

Show them where to find it on the drug facts table.

Makes sense.

What's number two?

Be skeptical.

You have to actively counter that ingrained belief that natural automatically means safe.

Explain that the NHPs can have powerful effects and dangerous interactions, just like prescription drugs.

Okay, read labels, be skeptical.

What's the third key message?

Tell everyone.

Patients absolutely must inform all their health care providers about everything they're taking.

That includes their doctor, nurse, pharmacist, dentist, chiropractor, everyone.

No exceptions.

Full disclosure is the only way to catch potential problems.

That comprehensive communication piece is vital.

And evaluation, what should patients be watching for?

They need a monitor for two things.

One,

is the product actually working?

Is there a therapeutic responsive version?

Less pain, better sleep, whatever the goal was.

But equally important, they need a monitor for adverse effects.

The source mentions things like nephritis, kidney inflammation, being linked to some herbals.

They need to know what warning signs to look out for and report them immediately.

Right.

So this whole area, OTCs and NHPs, it's far from simple or minor pharmacology.

Not at all.

It's complex and carries significant risks if not managed properly.

So quick recap of the biggest takeaways.

Okay.

One,

OTCs are regulated, yes.

But misuse is dangerous.

Especially know that acetaminophen limit, 4 ,000mg a day, and the risk of stacking.

Two, NHPs are not benign.

Their interaction potential is huge.

Think being coerphorin for bleeding, St.

John's wort messing with SSRIs, or acting as that chemical shredder for other drugs, grapefruit toxicity.

Screening is essential.

And the safety net.

Comprehensive patient assessment and education.

It's the only way to bridge the gap.

And maybe a final thought for our listeners.

The source mentions that even though many patients, maybe 60%, do ask a provider about choosing an OTC, a significant number still have adverse reactions, and very few actually report them.

So that vigilance piece is key.

It really is.

We worry a lot about prescription drug interactions, but sometimes the riskiest things are already in the patient's medicine cabinet or kitchen cupboard, bought without any professional oversight.

Our job is to uncover that.

That's the real deep dive, understanding everything the patient's actually taking.

That's a powerful reminder.

Thank you for joining us on this deep dive into the crucial world of non -prescription pharmacology.

Stay informed, stay vigilant, and we'll catch you on the next deep dive.