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Microbiome Changes in Healthy Volunteers


Call for Study Volunteers

The Garey Lab located at University of Houston College of Pharmacy is currently recruiting patients for study called, "Microbiome Changes in Healthy Volunteers." Antibiotic usage kills the bacteria (germs) that cause infections, but antibiotics can also kill the healthy bacteria that live in your body. These healthy bacteria are call your microbiota. Our study is investigating how certain antibiotics affect your microbiota.

Purpose of the Study

We are conducting this research to study microbiome changes associated with antibiotic use in
healthy volunteers.

Who can Participate?

  • Healthy adults aged 18-40
  • No history of cardiovascular, gastrointestinal, hepatic, renal disease, diabetes, vertigo, tinnitus, diminished hearing, depression, or coagulation disorders
  • Must be non-smokers
  • No antibiotic use for at least 3 months prior to enrollment
  • Not currently taking probiotics
  • Not pregnant or breastfeeding or planning on becoming pregnant in the next 20 days

What to Expect?

  • If you agree to participate, you will be given one of three antibiotics to take for 10 days
    The collection and storage containers will be provided to you to collect your stool samples for the 10 days you are taking antibiotics, the next 3 days after stopping antibiotics, and a follow-up visit at 1 month
  • Antibiotic will be provided to you daily when you visit the lab to drop off your stool sample
  • Saliva collection kit will also be provided at each visit to collect your oral microbiome

Possible Benefits and Risks of Participating

There are no direct benefits to participating but your results will improve our understanding of how antibiotics affect the healthy microbiome. The antibiotics we are testing are all FDA approved for the treatment of certain infections and are deemed safe and effective. However, all antibiotics have side effects. The possible side effects of each antibiotic will be explained to you. In exchange for your time and participation, we will provide VISA gift card for each stool and saliva sample provided ($40 per clinic visit / total: $560)


• Please contact our study coordinator Jinhee Jo at 713-743-2974 or via email (

UH IRB Approved (MOD00003241)