Turmeric, ginseng, a probiotic, even vitamin C — all of these, when taken in packaged form, are known as a supplement. These supplements have lined store shelves for decades. Others are ancient cures processed and packaged for 21st-century consumers.

Whatever their history, supplements are everywhere these days, and consumers are eating them up, spending billions each year on capsules, powders, and gummies. More than half of adults aged twenty (20) and older have taken one in the past 30 days, — and that percentage increases with age. About 80 percent of women over age 60 take a dietary supplement.

People may not realize that taking some of these supplements with their prescription drugs and other medicines can have dangerous and even life-threatening effects. Supplements can enhance, diminish, or negate a prescription drug in ways that can be consequential and unpredictable.

Research shows about 34 percent of survey participants — representing an average of seventy-two (72) million people in the United States — take some kind of dietary supplement along with a prescription medication.

Wondering which supplement-prescription pairings can be risky? We have compiled six (6) of the most popular supplements and their known effects on common medications.

1. St John’s Wort

Derived from a flowering shrub native to Europe, St. John’s Wort can be taken to treat mild to moderate depression, or to reduce menopausal symptoms such as hot flashes. But it has known drug interactions and can reduce the potency of birth control pills and hormone replacement therapy. It can also interfere with omeprazole (Prilosec), alprazolam (Xanax), certain statins and some antihistamines.

Moreover, St. John’s wort can render the COVID-19 antiviral treatment Paxlovid powerless. If a person is taking Paxlovid and St. John’s wort, which means essentially that the Paxlovid may not work.

2. CoQ10

Coenzyme Q10 (CoQ10) is an antioxidant produced by our bodies to promote cell growth and maintenance; the levels of it in our body can decrease as we age.

In supplement form, it can be taken as a capsule, tablet and or even a syrup for numerous conditions, including heart disease, diabetes and migraine. But CoQ10 can also interfere with the ability of blood thinners to do their job, which is to prevent blood clots from forming.

3. Turmeric

The ancient spice has been shown to have many health benefits, from improving memory to lowering inflammation and even decreasing the risk of heart disease. It also has anticoagulant effects, which means you do not want to mix turmeric supplements with a blood thinner or even aspirin, due to the risk of internal bleeding.

Ginkgo biloba (an herb) and vitamin E are two other dietary supplements that can thin the blood. So, taking them with an anticoagulant can increase the effect.

Cooking with turmeric? It is still fine to use in the kitchen. When products are used as foods, we do not think it is that much of an issue at all.

4. Probiotics

Full of beneficial bacteria, probiotics are taken to aid digestion and improve gut health. But do not take one within two hours of taking an antibiotic, or you could reduce the effectiveness of the prescription medication.

5. Vitamin C

Vitamin C occurs naturally in citrus fruits, strawberries, broccoli, and tomatoes, among other foods. It is also consumed as a supplement for a myriad of reasons, ranging from warding off the common cold to preventing cancer.

But high-dose vitamin C supplements may reduce the effectiveness of cancer chemotherapy. It can also interfere with niacin and statins and affect estrogen levels.

6. Milk thistle

A flowering plant related to daisies, milk thistle is taken as a supplement that promotes liver and heart health. It may also lower blood sugar, which could be a concern for someone who is on diabetes medication. When combined with insulin, it can be like taking a little bit too much glucose-lowering medication.

Bottom line: Talk to your doctor.

Ideally, to head off trouble, patients would be talking to their doctors about the supplements they are taking. But these conversations do not happen as often as they should!

A study in 2015 found that fewer than 50 percent of patients disclose the use of dietary supplements, and even among those who do, only about one-third of the supplements taken are mentioned to doctors.

One reason for the disconnect: Patients may not realize the over-the-counter herbs or extra vitamins they are working into their daily pile of pills count as anything that needs to be discussed with a doctor, so they leave them off the list when their provider asks. It is also not uncommon for consumers to confuse “natural” with “safe” and fail to fully recognize the potency of some of these products.

To help avoid any health hazards that can arise from mixing supplements and medications, it is important to ask your doctor about possible adverse reactions before starting any new medication or supplement. Greater awareness of the importance of discussing supplement use is needed in both providers and patients.

The FDA suggests bringing a list of everything you take — over-the-counter medicines (pain pills, allergy relief, etc.), dietary supplements and prescription drugs — with you to your next routine appointment to make sure your information is up to date. And be sure to keep track of the dosages and how many times a day you take them.

Also, if you are planning a surgery, do not be surprised if your doctor asks you to stop taking dietary supplements two or three works before the procedure to avoid changes in heart rate, blood pressure or bleeding risk.