Food Or Drink Interactions With Tamiflu And Keflex

In our latest question and answer, the pharmacist discusses whether or not there are food or drink interactions between Tamiflu and Keflex.


I'm on tamiflu and cephalexin. Can I drink orange juice and soda with them? And what food and drinks should I avoid? Thanks

Asked by ZBB On Mar 25, 2018

Answered by
Medical Content Reviewed By PharmacistAnswers Staff

On Mar 28, 2018

Both Tamiflu and Keflex (cephalexin) can safely be taken with orange juice or soda. There are no interactions reported.

In fact, there are no reported interactions with any type of food or drink with either Keflex or Tamiflu.

Food or fruit juice is sometimes recommended with both. If either isn't well tolerated or causing nausea, food may help alleviate symptoms.

Tamiflu (Oseltamivir)

Tamiflu (Oseltamivir) is an oral antiviral medication that is classified as a 'neuraminidase inhibitor'. It is indicated for both the treatment and prevention of the flu (i.e. influenza virus).

Data indicates that Tamiflu is most effective when started as soon as symptoms of the flu appear. The Centers for Disease Control and Prevention (CDC) states that Tamiflu therapy is most effective when started within 48 hours of illness onset. However, in certain high risk populations, it can be started later than 48 hours and still have benefit. 

Tamiflu is available in both a capsule form and a liquid form and is generally well tolerated but can cause the following side effects:

  • Headache
  • Nausea
  • Vomitting
  • Diarrhea
  • Confusion
  • Dizziness
  • Nightmares

The most common side effects of Tamiflu are GI related and may be helped if given with food.

Keflex (Cephalexin)

Keflex (cephalexin) is a 'first generation' cephalosporin antibiotic, which are chemically related to penicillins but have a broader antibacterial spectrum. Keflex is used for a wide range of bacterial infections but is most commonly used to treat respiratory and skin infections.

Keflex is generally well tolerated with GI side effects being the most common.

Taking Tamiflu With Keflex

Taking Tamiflu with Keflex is safe and there is no interaction between the medications. Using both together however, may increase the risk of GI side effects such as nausea and diarrhea. 

About the Pharmacist

Dr. Brian Staiger Pharm.D

Dr. Brian Staiger is a licensed pharmacist in New York State and the founder of He graduated from the University At Buffalo with a Doctor of Pharmacy degree in 2010. He has been featured in numerous publications including the Huffington Post as well as a variety of health and pharmacy-related blogs. Please feel free to reach out to him directly if you have any inquiries or want to connect! He's answered thousands of medication and pharmacy-related questions and he's ready to answer yours! Office: 716-389-3076

Recent Questions