What You Need to Know About Food and Drug Interactions

By January 4, 2018December 18th, 2019Health Insurance Member Resources Nutrition Well-being
Food and Drug Interactions

Despite what Mary Poppins said, a spoonful of sugar may not be the best thing to take your medication with.

What you eat and drink can affect the way medications work — and medications can also change the way your body uses certain foods. These food-drug interactions can:

  • Prevent a medicine from working the way it should
  • Cause a side effect from a medicine to get worse
  • Cause a new side effect

But it’s not just food — alcohol, caffeine, and other vitamins and supplements can affect how medicines work. Every time you use a medicine, carefully follow the information on the label and directions from your doctor or pharmacist.

Possible Side Effects

Take a look at these possible interactions that over-the-counter medicines, food, and alcohol can have with some common generic prescriptions. (Don’t see your medication listed here? Search the Drug Interactions Checker.)


Multivitamins and dairy products1,3,6

Drugs

Food

Interaction

Recommendation

Certain thyroid medications:
Levothyroxine
Dairy/calcium products, this may include some multivitamins
Decreased absorption, drug will not work as well
Take on empty stomach ½ – 1 hour before eating
Certain antibiotics:
Ciprofloxacin
Levofloxacin
Dairy products/calcium products, this may include some multivitamins
Decreased absorption, drug will not work as well
Avoid taking with dairy products. Separate by at least 2 hours

 

Leafy green vegetables/vitamin K3

Drugs

Food

Interaction

Recommendation

Certain blood thinners:
Warfarin
Spinach, kale, broccoli, cabbage, etc.
Doesn’t thin the blood as intended, which increases the risk of blood clots
Consume a steady amount of vegetables so warfarin dose can be adjusted to fit diet
Cranberry juice
Thins the blood more than intended, which increases the risk of bleeding
Avoid cranberry juice

 

Grapefruit juice2

Drugs

Food

Interaction

Recommendation

Certain drugs such as statins:
Atorvastatin
Simvastatin
Lovastatin
Grapefruit juice
Slows statin metabolism, which increases the likelihood of having side effects
Don’t drink more than 1 quart of grapefruit juice a day

 

Alcohol11,4

Drugs

Food

Interaction

Recommendation

Antihistamines:
Diphenhydramine
Chlorpheniramine
Alcohol
Increases drowsiness
Avoid alcohol
Acetaminophen
Alcohol
Increases risk of liver damage
Avoid alcohol
NSAIDs such as:
Ibuprofen
Naproxen
Alcohol
Increase risk of stomach upset/bleed
Avoid alcohol

 

Herbal supplements1,5

Herbal Products

Drugs

Interaction

Recommendation

Gingko Biloba
Garlic
Glucosamine
Warfarin
Increase risk of bleeding
Avoid while taking warfarin
St. John’s wort
Oral contraceptives
Cyclosporine
Indinavir
Warfarin
Digoxin
Benzodiazepines
St John’s wort can increase metabolism of these drugs
Avoid St. John’s wort

 

To help ensure your prescriptions have a chance to work as intended, always follow the directions and be sure to talk to your doctor, pharmacist, or other health care professionals if you have any questions.

This article was originally published on LinkedIn.

1 Avoid Food-Drug Interactions: A guide from the National Consumers League and U.S. Food and Drug Administration. S. Food and Drug Administration.
2 Grapefruit Juice and some Drugs Don’t Mix. S. Food and Drug Administration. [Online] Available at https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm292276.htm [Accessed 9 Nov 2017].
3 Bushra R, Aslam N, Khan AY. Food-Drug Interactions. Oman Medical Journal. 2011;26(2):77-83. doi:10.5001/omj.2011.21.
4 Metronidazole. Lexi-Drugs. Available at: https://online.lexi.com/lco/action/doc/retrieve/docid/patch_f/1798773# [Accessed 10 Nov. 2017].
5 Herb-Drug Interactions. National Center for Complementary and Integrative Health. [Online] Available at https://nccih.nih.gov/health/providers/digest/herb-drug [Accessed 13 Nov 2017].
6 Hulisz, Darrell. Food-Drug Interaction. U.S Pharmacist. 2007;32(3)93-98. [Online] Available at https://www.uspharmacist.com/article/fooddrug-interactions [Accessed 13 Nov 2017].

 

Harshal Amin

About Harshal Amin

I manage aspects of Independence’s Medicare Part D benefit and support clinical and quality improvement efforts. My goal is to help enhance the health and well-being of the communities that Independence serves.