Common OTC Medications: Uses, Side Effects, and Safety Tips You Need to Know

Every year, over 80% of adults in the U.S. reach for an over-the-counter (OTC) medication before calling a doctor. It’s quick, easy, and feels harmless-until it isn’t. You might think popping a few pills for a headache or runny nose is no big deal, but the truth is, OTC medications can cause serious harm if used incorrectly. They’re not candy. They’re not harmless. They’re drugs-powerful ones-and knowing how to use them safely could save your life.

What Exactly Are OTC Medications?

OTC medications are drugs you can buy without a prescription. They’re approved by the FDA and similar agencies worldwide for treating minor, self-diagnosable conditions like headaches, allergies, heartburn, coughs, and colds. But don’t be fooled by the label. Just because you don’t need a doctor’s note doesn’t mean these drugs are safe for everyone, all the time.

There are more than 100,000 OTC products on the market in the U.S. alone, containing around 800 different active ingredients. These are grouped into clear categories: pain relievers, cold and flu remedies, allergy meds, stomach treatments, and topical products like antiseptic creams. Each one has a specific purpose, a specific dose, and specific risks.

Pain Relievers: Acetaminophen vs. Ibuprofen

If you’ve ever had a headache or sore muscles, you’ve probably reached for either acetaminophen (Tylenol) or ibuprofen (Advil, Motrin). But they work very differently-and so do their risks.

Acetaminophen is great for reducing fever and easing pain. It’s often the go-to for kids, pregnant people, and those with stomach issues because it doesn’t irritate the gut like NSAIDs. But here’s the catch: it’s hard on your liver. Taking more than 4,000 mg in a day-even spread out over several doses-can cause severe liver damage. In fact, acetaminophen is the leading cause of acute liver failure in the U.S., with 15,000 to 18,000 emergency visits each year from overdoses. Many people don’t realize that acetaminophen is hidden in dozens of cold and flu products. Taking Tylenol for a headache and then a NyQuil for a cough? That’s a recipe for disaster.

Ibuprofen, on the other hand, is an NSAID. It reduces inflammation, which makes it better for sprains, arthritis, or menstrual cramps. But it can cause stomach bleeding, especially if taken on an empty stomach or for long periods. People with kidney problems, high blood pressure, or a history of ulcers should avoid it. The maximum daily dose is 1,200 mg for OTC versions. More than that? You’re stepping into prescription territory-and risk.

Bottom line: Use acetaminophen if you’re worried about your stomach or are pregnant. Use ibuprofen if you need to reduce swelling. Never take both together unless your doctor says so.

Cold and Flu: What Actually Works?

There are dozens of cold and flu meds on the shelf. But most don’t cure anything-they just mask symptoms. And some do more harm than good.

Pseudoephedrine (Sudafed) is one of the few effective decongestants. It shrinks swollen nasal passages. But it’s kept behind the counter because it can be used to make illegal drugs. You need to show ID and buy limited quantities. It can raise blood pressure and cause insomnia, so skip it if you have heart problems.

Dextromethorphan (Delsym, Robitussin) is a cough suppressant. It works for dry, hacking coughs. But it’s also abused by teens. Taking more than the recommended dose (usually 30 mg) can cause hallucinations, dizziness, and even coma. The FDA has warned about this for years, yet it’s still one of the most common OTC drug overdoses in adolescents.

Guaifenesin (Mucinex) is an expectorant. It helps thin mucus so you can cough it up. It’s generally safe, but it won’t make your cold go away faster. Drink plenty of water with it-it works better that way.

And skip multi-symptom formulas unless you have all the symptoms they claim to treat. Taking a product with antihistamines, decongestants, and pain relievers when you only have a sore throat? You’re overdosing on unnecessary chemicals.

Allergy Medications: The Drowsy vs. Non-Drowsy Divide

Allergy meds are where people make the biggest mistakes. First-generation antihistamines like diphenhydramine (Benadryl) work fast and cheap. But they make you sleepy-so much so that they’re often used as sleep aids. That’s dangerous. For adults over 65, diphenhydramine increases fall risk by 30%. It can also cause confusion, dry mouth, and urinary retention. The American Geriatrics Society lists it as a medication seniors should avoid.

Second-generation options like loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec) are far safer. They work just as well for sneezing and itchy eyes but cause little to no drowsiness. Loratadine is dosed at 10 mg once daily. Fexofenadine is 180 mg. Both are fine for long-term use in most people. If you’re on kidney medication, though, talk to your pharmacist. Fexofenadine may need a lower dose if your kidneys aren’t working well.

And don’t forget nasal sprays. Fluticasone (Flonase) is a steroid spray that reduces nasal inflammation. It takes a few days to work, but it’s more effective than oral antihistamines for congestion. It’s safe for daily use and doesn’t cause drowsiness.

Stomach Issues: Heartburn, Diarrhea, and Antacids

Heartburn is common. But treating it the wrong way can lead to bigger problems.

Antacids like Tums (calcium carbonate) give quick relief by neutralizing acid. Fine for occasional use. But if you’re taking them daily, you might be masking something serious like GERD.

H2 blockers like famotidine (Pepcid AC) reduce acid production. They last longer than antacids but aren’t as strong as the next level.

Proton pump inhibitors (PPIs) like omeprazole (Prilosec OTC) are the strongest. They block acid at the source. Great for frequent heartburn. But using them for more than 14 days in a row, or more than three times a year, can increase your risk of kidney disease, bone fractures, and vitamin B12 deficiency. A 2023 study in JAMA Internal Medicine found PPI users had a 20-50% higher risk of chronic kidney disease over time.

For diarrhea, loperamide (Imodium) slows bowel movements. It’s safe for short-term use. But if you have a fever, bloody stool, or it lasts more than two days, stop taking it and see a doctor. It can hide serious infections like C. diff.

Safety Rules You Can’t Ignore

Here’s what you need to remember every time you pick up an OTC medicine:

• Read the Drug Facts label. It’s not just filler. It tells you the active ingredient, purpose, uses, warnings, and directions. If you don’t know what’s in it, don’t take it.
• Check for duplicates. Many cold, flu, and pain products contain the same active ingredient. Taking two at once = overdose.
• Know your limits. Acetaminophen max = 4,000 mg/day. Ibuprofen max = 1,200 mg/day. Naproxen max = 660 mg/day. Don’t guess. Measure.
• Don’t use for chronic conditions. OTC meds aren’t meant for daily, long-term use. If you need pain relief every day for a month, see a doctor. You’re treating a symptom, not the cause.
• Watch for interactions. OTC meds can interfere with prescription drugs. For example, ibuprofen can reduce the effect of blood pressure meds. Antihistamines can worsen glaucoma or prostate problems.
• Store properly. Keep meds in a cool, dry place. Heat and moisture ruin them. Don’t leave them in the bathroom or car.
• Check expiration dates. Expired meds don’t work as well-and some can break down into harmful substances.

Special Populations: Kids, Seniors, and Pregnant People

Not everyone can take the same OTC meds.

Children under 4: The FDA bans cough and cold meds for this age group. They don’t work and have caused deaths. Use saline drops and a bulb syringe for congestion. Acetaminophen or ibuprofen (in child-appropriate doses) are fine for fever or pain.

Pregnant people: Acetaminophen is the only recommended pain reliever. Avoid NSAIDs after 20 weeks-they can affect fetal kidney development. Antihistamines like loratadine are considered safe. Avoid decongestants like pseudoephedrine in the first trimester.

Seniors over 65: Avoid diphenhydramine for sleep. It increases confusion and fall risk. Use melatonin or behavioral changes instead. NSAIDs can cause kidney damage and stomach bleeding in older adults. Always check with a pharmacist before taking anything new.

When to Call a Doctor

OTC meds are great for short-term relief. But they’re not a substitute for medical care. See a doctor if:

• Your symptoms last more than 7-10 days without improvement
• You have a fever over 102°F that doesn’t break
• You’re vomiting blood, passing black stools, or have severe abdominal pain
• You develop a rash, swelling, or trouble breathing after taking a med
• You’re taking more than the recommended dose for more than a few days

Many people delay seeing a doctor because they think OTC meds should fix everything. But if your body isn’t responding, it’s not because you need a stronger pill-it’s because you need a diagnosis.

The Role of Pharmacists

Pharmacists are your best resource for OTC safety. They’re trained to spot dangerous combinations, check for allergies, and recommend the right product for your situation. Nearly 93% of Americans live within five miles of a pharmacy. Use that resource. Don’t just grab the cheapest option off the shelf. Ask: "Is this safe for me?"

Many pharmacies now offer free OTC consultations. Some even use apps to scan your prescriptions and warn you about interactions. Take advantage of it.

What’s Changing in 2025?

Regulations are tightening. The FDA now requires clearer Drug Facts labels with bigger fonts and standardized wording. Some states are expanding pharmacists’ authority to prescribe certain OTC meds for minor conditions-like urinary tract infections or eczema-without a doctor’s visit.

Technology is also stepping in. CVS Health launched an AI tool called "OTC Advisor" that asks you about your symptoms, current meds, and health conditions, then recommends safe options. It’s not perfect, but it’s a step toward smarter self-care.

Still, the biggest problem remains: people think OTC means "safe." It doesn’t. It means "available." And availability doesn’t equal safety.

Use OTC meds wisely. Know what’s in them. Know your limits. When in doubt, ask a pharmacist. Your body will thank you.