Are OTC Medications Safe Over 65? Important Drug Interactions Adults Should Know!

Post By Samer Altameemi - A Licensed Pharmacist

Many adults over 65 take several prescription medications every day. When a headache, cold, heartburn, cough, or trouble sleeping develops, it's common to add an over-the-counter (OTC) product without thinking twice.

The problem is that OTC medications can interact with prescription drugs just like prescription medications interact with each other. In fact, some of the most common medication-related hospitalizations in older adults are linked to OTC products.

Understanding a few high-risk combinations can help prevent serious complications.

Why Seniors Are More Vulnerable to Drug Interactions

As we age, the body processes medications differently. Kidney function, liver function, and balance may change over time, making older adults more sensitive to medication side effects and interactions.

Many seniors also take medications for:

• High blood pressure

• Heart disease

• Diabetes

• Depression or anxiety

• Sleep disorders

• Blood clot prevention

Adding an OTC medication may seem harmless, but sometimes it can create unexpected problems.

Pain Relievers Are Not Always Risk-Free

Many people reach for Ibuprofen (Advil®) or Naproxen (Aleve®) for pain relief.

While effective, these medications can interact with:

• Blood thinners

• Blood pressure medications

• Diuretics ("water pills")

• Kidney medications

For example, combining ibuprofen or naproxen with blood thinners such as warfarin, apixaban, or rivaroxaban may significantly increase the risk of serious bleeding.

NSAIDs may also reduce the effectiveness of blood pressure medications and increase the risk of kidney injury.

Sleep Aids Can Increase Fall Risk

Many OTC sleep products contain Diphenhydramine or Doxylamine, ingredients found in products such as Benadryl®, Tylenol PM®, Advil PM®, and Unisom®.

When combined with:

• Sleep medications

• Anxiety medications

• Opioid pain relievers

the risk of excessive drowsiness, confusion, falls, and fractures increases substantially.

In older adults, diphenhydramine is one of the most commonly flagged medications during pharmacy medication reviews.

Cold and Sinus Medications Can Affect Blood Pressure

Many cold and sinus products contain Pseudoephedrine or other decongestants.

These ingredients may raise blood pressure and heart rate, making them problematic for people taking medications for:

• Hypertension

• Heart disease

• Certain heart rhythm disorders

If you have high blood pressure, always check with a pharmacist before choosing a cold or sinus medication.

Cough Medications Can Interact With Antidepressants

Many cough syrups contain Dextromethorphan, a common cough suppressant.

When combined with certain antidepressants such as Sertraline, Fluoxetine, and Venlafaxine, there is a risk of serotonin syndrome, a potentially serious condition that may cause:

• Agitation

• Sweating

• Rapid heart rate

• High fever

• Confusion

Although uncommon, this interaction is important to recognize.

Heartburn Products Can Affect Other Medications

Common antacids such as Tums® (Calcium Carbonate) and magnesium-containing antacids may interfere with the absorption of certain prescription medications.

Examples include:

• Levothyroxine (thyroid medication)

• Alendronate (osteoporosis medication)

• Certain antibiotics

The medications may still be taken together, but timing often matters.

Supplements Can Cause Interactions Too

Many people assume supplements are completely safe because they are sold without a prescription. However, some products may interact with prescription medications.

• St. John's Wort is particularly well known for reducing the effectiveness of many heart medications, blood thinners, and antidepressants.

• Ginkgo Biloba may increase bleeding risk when combined with blood thinners or aspirin.

• Potassium supplements may cause dangerously high potassium levels when combined with medications such as lisinopril, losartan, or spironolactone.

Questions Every Senior Should Ask Before Taking an OTC Medication

Before starting a new OTC product, ask yourself:

• Do I take a blood thinner?

• Do I have high blood pressure?

• Do I have kidney disease?

• Do I take medication for depression or anxiety?

• Do I take medication for sleep?

• Do I have heart rhythm problems?

• Do I take thyroid medication?

• Do I use diabetes medications?

• Do I take vitamins, minerals, or herbal supplements?

If the answer is yes to any of these questions, it may be worth checking with a

pharmacist first.

The Pharmacist's Takeaway

Most OTC medications are safe when used correctly, but they are not risk-free—especially for older adults taking multiple prescription medications.

The highest-risk OTC ingredients for seniors often include:

• Ibuprofen

• Naproxen

• Diphenhydramine

• Doxylamine

• Pseudoephedrine

• Dextromethorphan

• Certain supplements and herbal products

A quick conversation with a pharmacist before starting a new OTC medication can help prevent serious drug interactions and ensure the product is appropriate for your health conditions and prescriptions.

Found OTC  is your place to find smart over-the-counter solutions for common daily conditions, designed by the pharmacist.

Pharmacist Reviewed: the information in this article was clinically reviewed by Samer Altameemi, a licensed pharmacist. It is intended for educational purposes, not to substitute for a doctor's professional medical advice.

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