Don't Use Mouthwash If You're Taking These 2 Medications, Experts Warn

This seemingly harmless combination can have dangerous consequences.

From mixing the wrong pain relievers together to swallowing your pills with grapefruit juice, there are countless medication combinations that can do serious harm to our health. But even something as seemingly harmless and commonplace as mouthwash can be dangerous when mixed with certain prescriptions. In fact, doctors warn that you should avoid using mouthwash entirely if you're taking two specific medications. Read on to find out more about this troubling combination, and for more bad medication mixtures, If You Take These 2 OTC Meds Together, You're Putting Your Liver at Risk.

You shouldn't use mouthwash when taking two specific antibiotics.

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Most people know that they shouldn't be drinking alcohol while taking antibiotics, but some antibiotics are so potent they shouldn't even be taken with alcohol-containing products, like mouthwash. Jessica Nouhavandi, PharmD, a pharmacist and co-founder of online pharmacy Honeybee Health, told Insider that the antibiotics metronidazole (Flagyl) and tinidazole (Tindamax) have such a strong reaction with alcohol that people taking these antibiotics should even avoid using mouthwash. Metronidazole is an antibiotic used to treat a wide variety of bacterial and parasitic infections, and tinidazole is an antibiotic used to treat certain types of vaginal infections, according to WebMD. And for more medication concerns, If You Take This Medication, You're More Likely to Get a Blood Clot.

Using mouthwash with these antibiotics may cause strong side effects.

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Nouhavandi says mixing these two antibiotics with mouthwash is likely to produce strong side effects. In fact, according to WebMD, even a small amount of alcohol within a product like mouthwash can trigger side effects from these medications. As the site explains, "Metronidazole and tinidazole cause an intolerance to alcohol by altering how the body breaks down alcohol." In terms of side effects, you may experience throbbing in the head and neck, irregular heart beat, rapid heart beat, low blood pressure, sweating, nausea, and vomiting. And for more medication reactions, If You've Gained Weight Recently, This OTC Medication May Be to Blame.

These strong reactions can last for up to several hours.

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WebMD says these unwanted reactions can last from 30 minutes to several hours depending on how much alcohol you consumed. Fortunately, according to Nouhavandi, any side effects should usually disappear within a few hours. If they last longer or you think you are experiencing a severe reaction from mixing alcohol and antibiotics, you should contact your doctor immediately. And for more useful information delivered straight to your inbox, sign up for our daily newsletter.

You should wait three days after your last antibiotic dose to use mouthwash.

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According to Nouhavandi, you can continue using alcohol-based products like mouthwash three days after the last dose of your antibiotics. This is typically when the antibiotics have cleared from your system—so no negative interactions should occur. You should also not skip doses of your antibiotics or attempt to quit them early without talking to your doctor, per WebMD. And for more medication warnings, If You're Swallowing Your Medication With This, Stop Immediately.

Kali Coleman
Kali is an assistant editor at Best Life. Read more
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