Food and Drug Interactions to Avoid
Don’t eat this or drink that if you take any of these medications
If you’re taking a new medication, you’re smart enough to read the instructions about how much to take, when to take it and whether or not to take it with food. But be sure to read the fine print, too, because you may need to avoid certain foods or drinks while you’re on the drug to sidestep unwanted and potentially dangerous food-drug interactions.
Some foods and beverages, such as dairy, grapefruit juice and even leafy green vegetables, can alter the strength or effectiveness of certain medications. They may prevent your body from fully absorbing the medicine or they may have the opposite effect, potentially causing or worsening side effects, according to the Food and Drug Administration (FDA).
If you’re taking prescription or even over-the-counter medication, watch out for these food-drug pairings. Talk to your doctor or pharmacist for guidance about your particular medication and situation.
1. Statins, anticonvulsants and other drugsPhoto: Africa Studio/Shutterstock
Grapefruit juice doesn’t play well with most medications. “The juice modifies the body’s way of metabolizing the medication, affecting the liver’s ability to work the drug through a person’s system,” explain the authors of a paper on food-drug side effects. The result is more of the drug in your bloodstream — the same as taking a larger dose — and possibly increased side effects, according to the FDA. According to another paper on food-drug interactions, a person’s overall exposure to some drugs can be increased by more than fivefold the drug is taken with grapefruit juice.
The FDA recommends avoiding large amounts of grapefruit juice if you take certain cholesterol-lowering statins. People who take anticonvulsants should not drink grapefruit juice within a few hours of taking the medication. Drinking grapefruit juice is not recommended for people who take psychotropic drugs, which include some antidepressants.
2. BronchodilatorsPhoto: gresei/Shutterstock
These medications open the airways in people with health conditions, such as asthma, that cause breathing problems. But caffeine has the same effect (though of course a smaller one). People who use a bronchodilator are advised to avoid consuming large amounts of caffeine, found in coffee, chocolate and tea. The result could be nervousness and rapid heartbeat. High-fat meals may increase the amount of the drug in the body, while high-carbohydrate meals may decrease it. Alcohol can increase the drug’s side effects.
Related: 10 Foods to Eat for Eye Health
3. Antihistamines and pain relieversPhoto: lenetstan/Shutterstock
According to the FDA, antihistamines and alcohol don’t mix, since alcohol can make drowsiness, sometimes caused by these meds, worse.
If you’re going to drink alcohol while taking a pain reliever such as aspirin, ibuprofen, naproxen and acetaminophen, make sure you stick to the recommended daily limits of booze. The combo could increase the risk of liver damage, stomach bleeding and ulcers.The FDA recommends people who drink three or more alcoholic beverages per day consult their doctor before taking these drugs.
4. AntibioticsPhoto: Valentyn Volkov/Shutterstock
Milk doesn’t always do a body good. The calcium in milk can prevent antibiotics from being fully absorbed, so the FDA recommends avoiding milk, yogurt and calcium-fortified juices when you’re taking certain antibiotics. Talk to your doctor about your caffeine intake while you’re on antibiotics. The drugs could cause caffeine to build up in your body, according to the FDA.
Related: 6 Fresh Herbs for Better Health
5. AntidepressantsPhoto: al1962/Shutterstock
Antidepressants known as monoamine oxidase inhibitors (MAOIs) interact with foods that contain tyramine, such as aged cheese, yogurt and salami. In people taking MAOIs, high levels of tyramine can cause a sudden, dangerous increase in blood pressure according to the FDA. Many caffeinated foods and drinks also contain tyramine, as do many tap beers and red wines.
MAOIs include isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Emsam) and tranylcypromine (Parnate).
Also, don’t drink if you’re taking antidepressants, the FDA warns, since it can exacerbate potential side effects such as drowsiness.
6. Vitamin K agonists/anticoagulantsPhoto: hxdbzxy/Shutterstock
If you’re taking a blood thinner such as warfarin (Coumadin, Jantoven), you’ll probably need to watch your intake of certain greens, despite how good these foods are for your health. Sudden increases of foods rich in vitamin K can decrease the effectiveness of the drugs. Sudden decreases could increase warfarin’s effect, according to the National Institutes of Health. Vegetables rich in vitamin K include broccoli, Brussel sprouts, kale, asparagus and spinach. The trick is to maintain a steady level of vitamin K, so if you like to eat a lot of these foods, you’ll have to eat a lot of them every day.
Cranberry juice can decrease the warfarin’s effectiveness. And the FDA cautions patients to avoid garlic, ginger, glucosamine, ginseng and gingko while on warfarin because they can increase the risk of bleeding.
7. StatinsPhoto: ZEF/Shutterstock
A high-fiber diet can reduce the effectiveness of cholesterol-lowering statin drugs such as simvastatin (Zocor), ezetimibe (Zetia), pravastatin (Pravachol) and fluvastatin (Lescol). Oat bran, specifically, has been shown to lower the body’s absorption of certain statins. The FDA also recommends avoiding alcohol and large quantities of grapefruit juice while taking these medications.
8. ACE inhibitors and diureticsPhoto: Iurii Kachkovskyi/Shutterstock
Used to lower blood pressure and treat heart failure, ACE (angiotensin-converting enzyme) inhibitors relax blood vessels so blood can flow more freely. But they also increase the amount of potassium in the body and can be harmful when taken with foods high in potassium, such as bananas, oranges, green leafy vegetables and certain salt substitutes, according to the FDA. Too much potassium can cause an irregular heartbeat and heart palpitations, the FDA says.
The same goes for diuretics, which are prescribed to treat high blood pressure and reduce excess fluid and swelling caused by heart or liver problems. Since certain diuretics lower the kidneys’ ability to remove potassium, the FDA suggests avoiding foods high in potassium if you’re taking a diuretic.
9. GlycosidesPhoto: eZeePics/Shutterstock
These drugs, such as digoxin (Lanoxin, Digox, Digitek), control the heart rate and improve the strength of the heartbeat. They are used to treat conditions including congestive heart failure and atrial fibrillation. High-fiber diets can decrease digoxin levels, so the FDA advises taking digoxin at least two hours before or two hours after eating foods high in fiber. And don’t eat black licorice while on this medication. It contains glycyrrhizin, which can cause an irregular heartbeat or heart attack when combined with digoxin.
10. Thyroid medicinesPhoto: abc7/Shutterstock
If you take thyroid medicine for hypothyroidism, know that soybean flour (found in some infant formulas), walnuts and other high-fiber foods may decrease the absorption of the drug. If you make a change in your diet, let your doctor know.
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