For those on antibiotics

10 capsules


(ex. tax)
5/5 (15 reviews) Read the product reviews

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Suitable for





Dairy free

Dairy free

Gluten free

Gluten free

During pregnancy

During pregnancy

During breastfeeding

During breastfeeding


OptiBac Probiotics 'For those on antibiotics' is a high-quality probiotic supplement to help support gut health*. Contains two highly researched probiotic strains, Lactobacillus acidophilus Rosell-52 and Lactobacillus rhamnosus Rosell-11, which have both been shown to reach the gut alive alongside antibiotics.

for those on antibiotics press

Probiotic strains & ingredients

  • Lactobacillus rhamnosus Rosell-11
  • Lactobacillus acidophilus Rosell-52
  • Product description

  • How to use

  • Ingredients

  • Help & advice

  • Reviews

  • Product description

    Registered Nutritionist Naomi (ANutr) explains OptiBac 'For those on antibiotics'

    Who is 'OptiBac Probiotics For those on antibiotics' for​?

    For anyone looking to buy a natural probiotic supplement to take alongside a course of antibiotics.

    Key benefits

    • Each capsule provides 4 billion live cultures and the billions count is guaranteed until end of expiry.
    • The two strains contained in this supplement are very well researched for supporting gut & digestive health*.
    • Scientifically proven to survive stomach acidity and reach the gut alive, even when taken with antibiotics.
    • Easy to take on the go – no refrigeration required.
    • Suitable for women during pregnancy, vegans, vegetarians, and is gluten free for those with coeliac disease or an intolerance.
    • Safe to take and suitable from 1 year onwards.
    • Recommended for daily use over the course of 10 days alongside a typical course of antibiotics.
    • Free from artificial flavourings or colourings that may be found in other food & drinks containing probiotics.
    • Available in one pack size of 10 capsules.
    • From the UK’s most trusted & recommended brand of friendly bacteria supplements. As determined in an independent survey of 1000 British women+

    Once you have finished taking ‘For those on antibiotics’, we recommend taking ‘For every day EXTRA Strength’ as a daily supplement going forward.

    For every day Extra Strength

    Please note:
    This is a food supplement and is not intended to prevent, treat or diagnose any medical conditions.



    Customer feedback collected via independent review platform Trustpilot. See 'Reviews' tab for more customer opinions collected via our own website.

  • How to use

    Instructions for use

    Food supplement suitable for adults and children, from 1 year onwards, with the following recommendations:

    • Take 1 capsule daily with food, preferably with breakfast, every day during your antibiotic course and for a few days afterwards or until the pack has been completed.
    • Can be taken at the same time as antibiotics - this product has been clinically trialled alongside antibiotics and found to reach the gut alive.
    • Drink plenty of water with your course of live cultures.
    • For anyone unable to swallow capsules, the contents of the capsule can be mixed with a cold meal or beverage.

    Note: If you are taking particularly long-term antibiotics (a month or more), you may want to consider taking OptiBac For every day EXTRA Strength instead. This supplement would need to be taken with food, preferably breakfast, and 1 - 2 hours away from the antibiotic. 

    Food supplements should not be used as a substitute for a healthy diet and lifestyle. Those with serious medical conditions should consult their doctor before use. OptiBac will not cause dependency, and may be used on an ongoing basis.


    Like the rest of the OptiBac range, 'For those on antibiotics' does not require refrigeration. Store in a cool, dry place below 25°C and out of direct sunlight.


    Live cultures are not recommended for those with serious medical conditions e.g. those who are severely immunosuppressed, have pancreatitis, are in the ICU, have melaena, have a central venous catheter, infants with short bowel syndrome, or patients with open wounds following major surgery; unless under a doctor's care.



    Customer feedback collected via independent review platform Trustpilot. See 'Reviews' tab for more customer opinions collected via our own website.

  • Ingredients

    Ingredients for those on antibiotics supplement fact panel

    • Stabiliser: potato starch
    • Vegetarian capsule: hydroxypropyl methylcellulose
    • Live cultures: Lactobacillus rhamnosus Rosell-11, Lactobacillus acidophilus Rosell-52
    • Anti-caking agent: vegetable magnesium stearate; antioxidant: ascorbic acid

    Each capsule guarantees 4 billion live cultures.

    Suitable for vegetarian and vegan diets.

    Following the taxonomic updates advised by a global team of scientists and published in April 2020, a reclassification has been proposed for the rhamnosus species. The L. rhamnosus strain in 'For those on antibiotics' may therefore now also be known as Lacticaseibacillus rhamnosus Rosell-11.



    Customer feedback collected via independent review platform Trustpilot. See 'Reviews' tab for more customer opinions collected via our own website.

  • Help & advice

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  • Reviews

    Customer reviews

    • Excellent in rebalancing my gut health whilst taking antibiotics for tonsillitis. I have now gone on to use Optibac Max EveryDay as part of my continued recovery and I have noticed how both have helped in rebalance and recovery.

      Clementine Mary - 9th June 2020

    • I took these during a course of Metronidazol and it greatly reduced the side effects. Still had slight nausea, but no thrush this time.

      Lib - 15th March 2019

    • I took "For those on Antibiotics" during my H pylori treatment with two antibiotics. Although the antibiotics made me very tired and lose my appetite, I experienced no diarrhoea. The Optibac service was very helpful. I would definitely take these again if I am on antibiotics.

      Carrie - 17th April 2018

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