When you start to feel the pain of a urinary tract infection or strep throat, you may be prescribed a course of antibiotics in order to recover. Antibiotics may be needed for many types of bacterial infections, but what you eat while you’re on this medication can impact how well it works – and whether you’ll feel better.
Why Does It Matter What You Eat?
Certain foods can interact with an antibiotic by reducing how well it is absorbed by the body or even blocking the medication, while other foods can intensify side effects like gastrointestinal upset.
Antibiotics are a double-edged sword. Although these drugs can clear up your infection, they can also affect the natural balance of bacteria in your system. That can lead to the nausea, gas and diarrhea many people experience while taking antibiotics.
If you’re not familiar with a new medication, it’s always a good idea to ask for some guidelines from your pharmacist who is experienced at navigating food-drug interactions.
Lia Robichaud and Alicia Li, pharmacy interns at Samaritan Albany General Hospital, outlined some common foods that can impact antibiotics.
Foods Can Interfere With Antibiotics
Dairy and calcium-rich foods – Whether it’s cheese, milk, coffee creamer, yogurt or butter, the calcium in dairy products could be a problem. Tofu, kale and chia seeds are also high in calcium. When you eat these foods with certain antibiotics like tetracyclines or fluoroquinolones, the medicine can bind to the calcium which prevents it from being absorbed by your body. Space these foods to be at least two hours after you take your antibiotic and six hours before your next dose.
Fortified foods – Fortified foods can contain a high amount of calcium, creating the same problem that foods naturally high in calcium have – possibly interfering with your antibiotics. Common fortified foods include breakfast cereal, orange juice and non-dairy milk. Space these foods to be at least two hours after you take your antibiotic and six hours before your next dose.
High acid foods – Citrus fruits and juices like orange and grapefruit, soda, chocolate and tomato products have a high acid content, which could decrease how much medicine is absorbed into your system for certain antibiotics. Space these foods to be at least two hours after you take your antibiotic and six hours before your next dose. Caffeine – Some antibiotics can increase the effects of caffeine – and not in a good way. Antibiotics can keep your body from metabolizing the caffeine so it stays in your system longer. A cup of joe in the morning could lead to an increase in the diuretic effects of caffeine, jitters throughout the day and a sleepless night. Stick to noncaffeinated beverages while taking antibiotics, including plenty of water to stay hydrated.
Alcohol – Put cocktails or a glass of wine with dinner on hold. It’s best to completely abstain from alcohol until 48 hours after you’ve completed your course of antibiotics if you are taking metronidazole. Be on the lookout for alcohol or propylene glycol in mouth wash, cough medicine or cold and flu products, and avoid these as well. Consuming alcohol while taking certain antibiotics can cause severe nausea and vomiting, headache and other side effects.
Multi-vitamins and antacids – These products can contain minerals – primarily magnesium, calcium, aluminum, iron or zinc – that bind to the antibiotic and keep it from working. You may take multi-vitamins and antacids as long as you space them at least two hours after you take your antibiotic and six hours before your next dose.
What to Eat Instead
Soup – Enjoy broth-based soups that don’t rely on cream, cheese or tomatoes for flavor like chicken noodle, ramen, miso or lentil. These soups often have beneficial prebiotic foods like garlic, onion, vegetables and beans that help healthy bacteria regrow.
Bland foods – In general, foods for when you’re sick are also appropriate when you’re taking antibiotics. Plain or lightly salted crackers, peanut butter and non-citrus fruit are good choices. The BRAT diet (bananas, rice, applesauce, toast) can help with diarrhea from antibiotics.
Water – Staying hydrated is important, especially when you’re sick. It helps your body fight the infection, your medication to work properly and to combat some of the gastrointestinal side effects of antibiotics.
Fermented foods – Sauerkraut, kimchi, miso, fermented vegetables and kombucha contain beneficial probiotics that can support your gut and can help offset some of the unpleasant side effects of antibiotics. Yogurt and kefir can also be helpful, particularly the Nancy’s brand. Ensure dairy products are appropriately spaced from your antibiotic.
Probiotic supplements – Taking probiotics while you’re on antibiotics can help provide beneficial bacteria to your system and may also help with diarrhea. Some common brands include Culturelle, RenewLife and Florastor. If your provider prescribes probiotics with your antibiotic, they can be taken at the same time and don’t need to be spaced. Otherwise, follow the directions on the label. Your provider may recommend taking a probiotic supplement for up to a week after finishing your course of antibiotics.
Take Antibiotics Properly
- Always follow the instructions on the medication label. Always finish your regimen, even if you start to feel better. Don’t save antibiotics for another time.
- Some antibiotics should not be broken, crushed or chewed, so check the label. If you have trouble swallowing pills, tell your provider who can discuss other options with you.
- If you miss a dose, take it as soon as you remember unless it’s almost time for your next dose, about three to four hours. Doses are timed to keep a consistent amount of medicine in your body. Taking the doses too close together or taking a double dose can increase your side effects and doesn’t have any benefit.
- If you miss all of your doses in a 24-hour period, call your provider.
- If the label says to take with food, you can take your medicine with a meal or a little snack like crackers and fruit. Food helps the body to absorb certain medications and can reduce side effects.
- If the label says to take on an empty stomach, time your meals to be either one hour after you take the medicine or two hours before your next dose. Some medicines work better if there is no other food in your stomach.
After You’re Finished With Antibiotics, Help Healthy Bacteria Grow
According to a study of intestinal bacteria published in the journal Clinical Infectious Diseases, gut microbiota mostly repopulate within two to four weeks of finishing a course of antibiotics. However, it can take up to a year or longer for your gut microbiome to fully recover.
Other bacterial colonies on your body can also be affected by antibiotics. For example, women can occasionally develop a yeast infection after a round of broad-spectrum antibiotics, because the antibiotics clear out beneficial bacteria in the vagina.
You can encourage a diverse population of beneficial bacteria to regrow and keep you healthy by making prebiotic and probiotic foods a priority. It’s also helpful to limit sugar and processed foods for several weeks, as these can suppress healthy bacterial growth.
Antibiotics are sometimes necessary but the medical community is still learning the full long-term effects on the body. Take your medicine as prescribed and talk to your pharmacist if you have any questions about the right way to take antibiotics.
Work with a pharmacy you trust. Find a Samaritan Pharmacy location near you.