Drug interactions 101: what to know and how to best protect yourself

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Help stay safe while staying healthy!

Modern medicine is amazing. Conditions that were once debilitating can now be managed, often much easier than what was once thought as possible.

Among the most significant advancements in health care is the development of prescription drugs. They can help fight infection, reduce pain, improve mood, reduce the effects of high blood pressure, control long-term diseases such as diabetes or heart disease, and many other benefits.

But as we get older, the likelihood of taking prescriptions grows. For some, it’s one a day; for others, it may be a few. And generally speaking, we take our medications as directed, go about our day, and all is good.

However, sometimes they can cause unwanted reactions. And while many drug interactions are minor, some can be serious. That’s why being mindful of any potential drug interactions is so important.

Before we get started …

The contents of this article are intended for informational and educational purposes only and not for the purpose of rendering medical advice. Please seek the advice of a physician or other qualified health care providers with any questions regarding a medical condition or any medications.

What are drug interactions?

This is when a drug doesn’t interact well with something else in your body. Drug interactions can make your medication too strong, stop working as well as it normally does, or make it stop completely. It could also cause side effects (or magnify them).

Types of drug interactions

Food/drink + drug interaction

A reaction between a drug and a food or beverage. (This could also include any over-the-counter supplements.)
Drug + drug interaction

A reaction between two (or more) drugs.
Drug + condition interaction

A reaction that occurs when taking a drug while having a certain medical condition. For example, taking a nasal decongestant if you have high blood pressure may cause an unwanted reaction.

Signs of a drug interaction

While many side effects of a drug interaction can be minor, others can be serious so it’s important to pay attention. Here are some of the more common symptoms:

Drowsiness
Dizziness
Nausea or vomiting
Diarrhea
Muscle aches, pains or breakdown
Depression, confusion or memory loss

Increased bruising or bleeding
Abnormal heart rate
Skin rash
Liver damage
Anxiety or restlessness
Your medicine may not be working as well

If you think you’re experiencing these due to a drug interaction, contact your doctor right away.

Common drug interactions

Here are a few examples of common foods or prescriptions that may cause side effects for people.

Alcohol

According to the National Institutes of Health, dozens of common medications have the potential to interact in dangerous ways with alcohol. These include psychotropic drugs for anxiety, sleep, or antidepressants, opioids, anticoagulants and cardiovascular prescriptions, antimicrobials, over-the- counter (OTC) pain medications (such as ibuprofen and acetaminophen), and more. In fact, about 80% of people age 65 and over have taken a medication in the past year that could interact with alcohol.

Grapefruit

Rich in antioxidants, vitamins, and fiber, grapefruit is delicious and nutritious. However, it can be problematic when it comes to interacting with drugs. Notably, it’s been known to interact with a number of statins (but not all); however, research shows that grapefruit can interact with up to 85 medications.

Warfarin

This anti-coagulant medicine can be a lifesaver, but there are quite a few things that will interact with it. OTC medications include aspirin, acetaminophen, ibuprofen and more. Likewise, there are a number prescriptions that may interact with it as well. These include antibiotics, COVID- 19 treatment, anti-fungal treatments, medicines to treat irregular heart rhythms such as amiodarone, and seizure medicines. Lastly, it’s worth noting that a number of foods and natural supplements may interact with warfarin, too:

Alcohol
Black licorice
Cranberries or cranberry juice

Garlic
Ginkgo biloba
Grapefruit

Green tea
Vitamin E
Vitamin K

For vitamin K, try to maintain a regular diet that includes foods rich in vitamin K (lettuce, spinach, broccoli) without altering the levels from day-to-day or week-to-week. A sudden change in vitamin K levels may alter the warfarin you need.

Levothyroxine

This prescription for hypothyroidism can be impacted by a wide variety of medications. Count antiarrhythmics, antacids (containing aluminum, magnesium or calcium carbonate) and proton pump inhibitors (omeprazole, lansoprazole, esomeprazole, etc.), anticoagulants, beta-blockers, cancer medications, corticosteroids, medications for cough and cold symptoms or for weight loss, insulin or other medications to treat diabetes, and tricyclic antidepressants (such as amitriptyline) as prescriptions that may react with it.

For people who take an iron supplement while on a prescription for levothyroxine, it’s important to coordinate the timing of your supplement with your prescription.

St. John’s Wort

While there’s been some research that shows St. John’s Wort seems to be more effective than a placebo for helping treat mild to moderate depression, it’s not an approved medicine by the FDA. This natural supplement has been known to interact with antidepressants, cyclosporine (which prevents the body from rejecting transplanted organs), heart medications (including digoxin and ivabradine), HIV drugs, cancer medications, including irinotecan and imatinib, Warfarin, and certain statins, including simvastatin.

Three ways to help minimize the risk of a drug interaction

You don’t have to be a medical expert to help reduce your risk of a drug interaction. But being your own No. 1 advocate can go a long way in making sure you’re taking the right steps to reduce your chances of a drug interaction.

Here are three simple steps to do just that.

1. Talk to your doctor.

It may seem like a no-brainer, but over-communicating with your doctor is a good starting point. That way, he or she knows all the medicines, vitamins, and supplements you’re taking. And if you have more than one doctor prescribing medications (e.g., your primary care physician and cardiologist), it’s even more important.

Don’t rely on memory. Write a list of your medications in advance of your appointment or take the medicine packages with you.

2. Talk to your pharmacist.

Pharmacists are often unsung heroes of the medical world and their expertise on drug safety can help protect you. They can also explain details or put medical jargon in everyday language. Before taking a new medication, ask questions such as …

“Can I take this with my other meds?”
“Should I avoid certain foods, drinks, or other products?”
“Could this medication interact with any health conditions I have?”

3. Do your own due diligence.

Give yourself a few minutes to review active ingredients and drug safety instructions. If you’re not sure of something, always double-check with your doctor or pharmacist. As the saying goes, a stitch in time, saves nine.

Online drug interaction checkers are widely available from reliable sources such as WebMD, Mayo Clinic and some larger pharmacy chains. They’re no replacement for talking to a medical professional, but they can be helpful.

In short … talking to your health care team and paying attention to the small details can make all the difference in the world.

Here’s to your health!