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Dangers Lurking in Your Medicine

Just because it’s prescribed, doesn’t mean it’s safe.
FACT CHECKED BY Emilia Paluszek

Are you aware of potential dangers linked to your prescription and over-the-counter medications? "Every person has a unique set of circumstances, a unique set of disease states, is taking different drugs, and reacts to medications in a unique way. You can't say that just because a drug that is safe for someone else, it will be safe for you," says William Churchill, chief of pharmacy services at Harvard-affiliated Brigham and Women's Hospital. Here are five dangers connected to common medications, according to experts. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

1

Mouthwash

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Alcohol-based mouthwash can pose serious risks to your health, experts say. "Think of mouthwash as the equivalent of unnecessary antibiotics in your mouth," says Mark Burhenne, DDS. "In the same way that antibiotics totally disrupt the balance of bacteria in your gut (which can lead to poor immune function and a host of other problems), mouthwash destroys all bacteria indiscriminately. And just like you need them for gut health, you need good bacteria to support your oral microbiome, which can decrease the risk for common issues like cavities, gingivitis, and bad breath."

2

Prescription Opioids

Woman holding a pill in her hand.
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"What makes opioid medications effective for treating pain can also make them dangerous," says Carrie Krieger, PharmD. "At lower doses, opioids may make you feel sleepy, but higher doses can slow your breathing and heart rate, which can lead to death. And the feelings of pleasure that result from taking an opioid can make you want to continue experiencing those feelings, which may lead to addiction. You can reduce your risk of dangerous side effects by following your doctor's instructions carefully and taking your medication exactly as prescribed. Make sure your doctor knows all of the other medications and supplements you're taking."

3

Grapefruit

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Grapefruit can interfere with prescription medications, experts warn. "Grapefruit and certain other citrus fruits, such as Seville oranges, can interfere with several kinds of prescription medications," says Katherine Zeratsky, RD, LD. "Don't take these interactions lightly. Some can cause potentially dangerous health problems. If you take prescription medication, ask your doctor or pharmacist whether your medication interacts with grapefruit or other citrus products. Problems arise because chemicals in the fruit can interfere with the enzymes that break down (metabolize) the medication in your digestive system. As a result, the medication may stay in your body for too short or too long a time. A medication that's broken down too quickly won't have time to work. On the other hand, a medication that stays in the body too long may build up to potentially dangerous levels."

4

Beware of New Ingredients

Grapefruit thyme glazed root veggies
Courtesy of Foraged Dish

With so many new supplements containing new, untested ingredients, it can be incredibly difficult to gauge how safe—or dangerous—they might be. "The problem that we've had recently, in recent years especially, is that there's been an explosion of new ingredients," says Pieter Cohen, MD, an internist at Cambridge Health Alliance and associate professor of medicine at Harvard Medical School. "So, it's not only that we're worried about the ingredients that are legal and permitted in supplements or historically used in supplements for many years, but that there are many of these ingredients—these are individual compounds found in botanicals or other substances—that can pose health risks. Nowadays we're seeing so many new innovations or brand-new ingredients being introduced to supplements. Again, because the FDA isn't vetting these products before they show up on store shelves or on the internet, what happens is that they can pose unpredictable risks."

5

OTC Painkillers

Female doctor talking while explaining medical treatment to patient through a video call with laptop in the consultation.
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People taking over the counter pain medication should be careful to follow dosage instructions and keep track of the time painkillers are taken to avoid accidental overdose. Over the counter medication is real medication—and can have serious side effects. "OTCs can increase blood pressure, pose cardiac risk, worsen asthma and complicate infections," says pharmacist Dean Mercer.

Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more about Ferozan
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