OptiBac Probiotics 'For those on antibiotics' has been created especially for those wishing to take natural bacteria during a course of antibiotics. It contains the strains L. rhamnosus Rosell-11 & L.acidophilus Rosell-52 which are both proven to reach the gut alive, even during a course of antibiotics. Suggested for daily use, each capsule provides 4 billion live microorganisms guaranteed until end of expiry. The strains within OptiBac Probiotics 'For those on antibiotics' are extremely well-researched alongside antibiotics, and are even safe to take at the same time as antibiotics. Each pack contains 10 capsules. It is important to note that this supplement, unlike many products containing live cultures, does not require refrigeration, due to improvements in freeze drying techniques as well as the strains within the product being naturally robust and able to survive harsher conditions. All OptiBac Probiotics strains are thoroughly researched and documented, so you can be confident you're getting a high quality supplement, which is proven to reach the gut alive.