Healthy Aging – Food and Drug Interactions

The average adult older than 65 regularly takes more than four prescription medications and two over-the-counter medications at one time. In fact, older Americans buy 30 percent of all prescription drugs and 40 percent of all over-the-counter drugs, according to the Food and Drug Administration. These drugs treat health problems, but they also can interact with each other and with food you eat.

Some foods affect how a drug is absorbed or used in our bodies. Medications also can influence how the body handles food. Listed below are common medications that interact with food, but you also should talk to your doctor about side effects or interactions with your medications.

  • Analgesic or anti-inflammatory drugs (such as aspirin, ibuprofen, Tylenol, Aleve):
    • These drugs are absorbed best on an empty stomach, but you can take them with food if they cause an upset stomach.
    • You may need more vitamin C, folate and vitamin K because aspirin competes with these vitamins.
  • Antibiotics (such as penicillin, erythromycin, tetracycline):
    • Penicillin and erythromycin may be poorly absorbed if taken with acidic foods like caffeinated drinks, tomatoes and fruit juice.
    • Tetracycline is absorbed best on an empty stomach, but can be taken with food if it causes an upset stomach.
    • Eat dairy products at a different time than tetracycline for best absorption of the drug.
    • When taking antibiotics, you may need extra nutrients because they may cause diarrhea and interfere with your body’s ability to feel hunger.
  • Anticancer drugs (chemotherapy agents):
    • These drugs decrease hunger, cause diarrhea and may cause you to be sick to your stomach. You may need more nutrients when on this treatment.
  • Anticoagulants (blood thinners such as coumadin):
    • Vitamin K helps blood clot; too much vitamin K interferes with blood thinning drugs. Avoid foods high in vitamin K like broccoli; green, leafy vegetables; asparagus; and liver.
    • Mineral oil decreases the absorption of vitamin K and may make a blood-thinning drug too strong.
    • Ask your doctor about vitamin E supplements before taking any. High doses of vitamin E may increase risk of bleeding.
  • Antidepressants (such as MAO’s or monoamine oxidase inhibitors):
    • Avoid foods high in tyramine such as alcoholic beverages, non-alcoholic beer and wine, aged cheese, processed American cheese, avocadoes, bananas, caffeine drinks, sour cream, liver, yeast products, dried and pickled fish, sauerkraut, soy sauce and cured meat. Tyramine may cause a dangerous increase in blood pressure when combined with these drugs.
  • Antihistamines (such as Benedryl, Allegra, Claritin, Zyrtec):
    • Take prescription antihistamines on an empty stomach.
  • Antihypertensives (such as lopressor, ACE inhibitors and other high blood-pressure drugs):
    • Natural licorice flavor, which comes from licorice root, can increase blood pressure. Artificial flavoring does not.
  • Bronchodilators (such as theophylline, for certain breathing problems):
    • High-carbohydrate, high-fat or high-protein meals may change drug absorption.
    • Large amounts of caffeine along with bronchodilator drugs may overstimulate the nervous system.
    • Alcohol can cause vomiting, headaches and irritability if taken with bronchodilators.
  • Corticosteroids (such as prednisone, hydrocortisone, deltasone):
    • These drugs, which are prescribed for many illnesses, may cause stomach upset. Take them with food or milk.
    • Choose low-sodium foods. These medications make the body retain too much sodium and water, causing edema (body swelling).
    • Long-term corticosteroid use may cause protein, potassium, calcium, magnesium, zinc, vitamin C and vitamin B6 loss.
  • Diuretics, potassium-wasting (like Lasix):
    • This drug may cause loss of potassium and change the body’s salt levels.
    • Good food sources of potassium include bananas, potatoes, dairy products and other fruit and vegetables.
  • HMG-CoA reductase inhibitors (Lipitor, Baycol, Zocor, and other cholesterol-lowering drugs):
    • Large amounts of alcohol taken with these medications may increase risk of liver damage.

This list is provided by Colorado State University Cooperative Extension and the FDA. This information does not replace advice from your health-care provider. To help protect your health, check with your pharmacist for a more complete list of medication interactions, and tell your doctor and pharmacist about all the medications and supplements you are taking, including vitamins, minerals and herbs.

No endorsement of products mentioned is intended nor is criticism implied of products not mentioned.

More information can be found on the Colorado State Cooperative Extension fact sheet No. 9.361 or on the FDA Web site at

Additional articles on Healthy Aging are available on the Colorado State University Cooperative Extension Web site. Go to then click on the Consumer/Family link under Information Online.