Taking a new medication may mean switching up your lifestyle a bit — and that includes the foods you eat. A food-drug interaction means that a specific nutrient or compound within the food changes the way your body metabolizes the medication, and this can either enhance or reduce the dose your body gets, according to Johns Hopkins Medicine. The potential results: an increased risk of side effects, many of which can be dangerous, or the drug not working as it was intended.
Before introducing a medication, ask your pharmacist about any food interactions, including with alcohol, and any adjustments you may have to make to your diet. Here are 10 medications that interact with food, plus what you can do to stay safe.
1. Acetaminophen + Alcohol
If you’re popping Tylenol (acetaminophen) after drinking to ward off a hangover, you may be putting yourself in danger. “When combined with alcohol, you may be at an increased risk of liver toxicity,” says Jessica Nouhavandi, PharmD, Co-CEO and cofounder of Honeybee Health in Culver City, California. This risk is highest if you are a regular drinker and use acetaminophen daily, and she says especially avoid this combination if you drink more than three alcoholic beverages a day. (The Centers for Disease Control and Prevention recommends that men and women limit themselves to two and one drinks per day, respectively.)
2. Some Antibiotics + Dairy
Nouhavandi says certain antibiotics shouldn’t be taken alongside milk, yogurt, or cheese. “Dairy products bind to the medicine and interfere with its absorption in the bloodstream,” she says. This goes for fluoroquinolones like Cipro (ciprofloxacin), Levaquin (levofloxacin), Avelox (moxifloxacin), and certain tetracyclines. Avoid eating that bowl of yogurt or ice cream at least two hours before and six hours after taking your antibiotics, Nouhavandi advises.
3. Calcium Channel Blockers and Statins + Grapefruit
Calcium channel blockers are used for high blood pressure and angina, explains Harvard Health Publishing. Some, including Plendil (felodipine) and Procardia or Adalat (nifedipine), are known to interact with grapefruit juice. This also happens with statins used for high cholesterol, such as Lipitor (atorvastatin) and Zocor (simvastatin). “Grapefruit contains a compound that inhibits a common drug-metabolizing enzyme called CYP3A4. Drinking a lot of the juice or eating the fruit inhibits this enzyme, and the drug accumulates in your system, which can be dangerous,” says Aaron Emmel, PharmD, founder of PharmacyTechScholar.com in St. Augustine, Florida. This does not happen with other citrus, so you can confidently sip orange juice instead.
4. MAOIs + Aged Cheeses
If you take an antidepressant that’s a monoamine oxidase inhibitor (MAOI), such as Marplan (isocarboxazid), Nardil (phenelzine), Emsam (selegiline), or Parnate (tranylcypromine), you’ll need to watch high-tyramine foods in your diet. Tyramine is an amino acid involved in blood pressure regulation, according to the Mayo Clinic. “This combination can cause a hypertensive crisis,” says Emmel. High-tyramine foods include aged cheeses, specific types of wine, pickled herring, brewer’s yeast, and fava beans, he notes. That said, MAOIs are not as frequently prescribed as other types of antidepressants (like selective serotonin reuptake inhibitors, or SSRIs), and if this interaction is a worry for you, talk to your doctor about other options.
5. Ziprasidone + Small Meals
Geodon (ziprasidone) is an antipsychotic used to treat bipolar disorder and schizophrenia. You’ll want to take it with a meal of at least 500 calories, notes the National Alliance on Mental Illness. As one study shows, eating it with a substantial snack or meal optimizes absorption of the drug so it can work most efficiently, says Howard.
6. Hypothyroid Drugs + (Any) Food
If you have been diagnosed with hypothyroidism (an underactive thyroid), you are probably taking Synthroid (levothyroxine) to restore your levels. There’s a reason that the label instructs you to take this first thing in the morning with a 30- to 60-minute buffer before consuming any food: “There are about a dozen different dosages your doctor can prescribe. That’s because the dosage has to be just right for your thyroid to function correctly,” says Ashley Ellis, PharmD, director of clinical operations at Compwell in Collierville, Tennessee. Food can block absorption of the drug in your small intestine, effectively lowering your dose in a way that will affect your thyroid, she explains. Unfortunately, yes, this includes coffee, too.
7. Spironolactone + Licorice
Aldactone (spironolactone) is a diuretic used to treat low potassium and heart failure, according to MedlinePlus. Take stock if you consume licorice tea, candy, or supplements. “Licorice competes with the same receptors as spironolactone, which makes the drug ineffective,” says Ellis. She recommends avoiding licorice in food or supplement form if you’re taking this water pill.
8. SSRIs + Alcohol
As mentioned, SSRIs are antidepressants that treat depression. They can also help treat anxiety. But using alcohol to quell the symptoms of anxiety or depression can lead to severe problems. “The risk of combining these with alcohol is stomach or gastrointestinal bleeding,” says Ellis. She calls this a “black box warning,” meaning it’s mandatory for the pharmacy to warn patients about this interaction.
9. Warfarin + Kale
Jantoven and Coumadin (warfarin) are blood thinners to treat blood clots. Vegetables like kale and broccoli pack in vitamin K. The problem is that “vitamin K negates what warfarin is trying to do,” says Mitchell Howard, PharmD, clinical assistant professor at the University of Toledo College of Pharmacy and Pharmaceutical Sciences. Without warfarin working properly, your risk of a blood clot increases. You don’t have to avoid vitamin K — that’s a common misnomer. Rather, “your diet needs to stay consistent,” says Howard. If you are eating more produce because of the season or suddenly stop eating many vegetables, you could suffer side effects like blood clots or bleeding. In that case, your doctor can adjust your medication dose.
10. Metronidazole + Alcohol
Metronidazole (Flagyl) is used to treat infections, including the vaginal infection bacterial vaginosis, according to the Mayo Clinic. Do not — and this bears repeating, do not — drink any alcohol while on it, as it interferes with alcohol metabolism. “This combination causes severe vomiting,” says Ellis. She recommends waiting 48 hours after stopping the medication before having that glass of wine.