For Those On Antibiotics Probiotics

30 capsules


(ex. tax)

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Suitable for



Gluten free

Gluten free

During pregnancy

During pregnancy

Dairy free

Dairy free

GMO free

GMO free

During breastfeeding

During breastfeeding

See full ingredients list


Optibac Probiotics For Those On Antibiotics is a high-quality probiotic supplement formulated to help support gut health*. Contains highly researched probiotic strains, which have been shown to reach the gut alive even when taken alongside antibiotics.

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Probiotic Strains

  • Lactobacillus rhamnosus Rosell-11
  • Bifidobacterium lactis Lafti B94
  • Lactobacillus acidophilus/helveticus Rosell-52
  • Product Description

  • How To Use

  • Ingredients

  • Help & Advice

  • Reviews

  • Delivery & Returns

  • Product Description

    Probiotics to take with antibiotics

    Great for anyone looking for a natural probiotic supplement to support their gut health during a course of antibiotics.

    Key benefits

    • Suitable alongside antibiotics – contains three strains of probiotic bacteria which have been studied in clinical trials involving probiotics and antibiotics
    • Highly researched for gut health – all three strains have been shown to support gut health & digestion and complement the natural gut bacteria*
    • Specific strain actionL. rhamnosus Rosell-11 and L. acidophilus/helveticus Rosell-52 also increase immune cell activity*
    • Scientifically proven – shown to survive stomach acidity and reach the gut alive, even when you take these probiotics with antibiotics
    • For daily use – designed for daily use with a typical 10-day course of antibiotics, or can be used for longer periods alongside long-term antibiotics
    • Easy to take – each easy-to-swallow capsule contains 4.5 billion live bacterial cultures; take on the go with no need for refrigeration 
    • A more natural option – vegan and gluten free, with absolutely no artificial flavourings or colourings, and suitable from 1 year of age including during pregnancy
    • Highly recommended – from the UK’s most trusted & recommended brand of probiotic supplements, as determined in an independent survey of 1000 British women+

    Product reviews


    Customer feedback collected via independent review platform Trustpilot. See more For Those On Antibiotics reviews for more customer opinions collected via our own website.

  • How To Use

    Recommended use

    • Take 1 capsule daily with food, preferably with breakfast, throughout your antibiotic course and for a few days afterwards, or until the pack has been completed – can be used on an ongoing basis for those on long term antibiotics.
    • Can be taken at the same time as antibiotics - strains in this product have been clinically trialed alongside antibiotics and found to reach the gut alive.
    • Drink plenty of water with your course of probiotics.
    • For anyone unable to swallow capsules, open and mix contents of the capsule with a cool meal or beverage.

    Storage instructions

    • Store in a cool, dry place below 25°C (77 °F) and out of direct sunlight.


    Live probiotic 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. Keep out of reach of children.

    This is a dietary supplement and is not intended to diagnose, treat, cure or prevent any disease. Food supplements should not be used as a substitute for a healthy diet and lifestyle. If you are taking any medications or have a serious medical condition, consult a doctor before use. Optibac supplements will not cause dependency and may be used on an ongoing basis.

    Customer Questions

    All questions answered by probiotic experts Dr Kate Stephens PhD (Food and Microbial Sciences) BSc (Hons) Medical Microbiology and Kerry Beeson BSc (Nut. Med.) Nutritional Therapist.

    Can I take probiotics with antibiotics?

    Yes, it is absolutely fine, and advisable, to take probiotics whilst on antibiotics. This is a particularly good time to support gut health. However, only certain probiotic strains are suitable to take alongside antibiotics, so it’s best to select supplements containing strains such as Lactobacillus acidophilus/helveticus Rosell-52 and Lactobacillus rhamnosus Rosell-11, and Bifidobacterium lactis Lafti B94 which have been extensively researched alongside this type of medication1,2.

    Which probiotics are best to take with antibiotics?

    Many probiotic strains aren’t robust enough to take alongside antibiotic medication, so it’s important to choose strains that have been trialed alongside antibiotics and shown to reach the gut alive. Probiotic strains in For Those On Antibiotics, have been shown to do so in numerous clinical trials, even when taken at the exact same time as antibiotic medication1. These high-quality strains have been clinically trailed at various life stages, including in children2,3, and can be taken during long or short courses of antibiotics.

    When should I take probiotics with antibiotics?

    Like most of our probiotic range, we recommend that For Those On Antibiotics, should be taken at breakfast time. It’s fine to take this supplement with breakfast and alongside your antibiotics at the same time. If you take your antibiotics at a different time of day, then still take For Those On Antibiotics with breakfast. If you choose to take a different probiotic supplement, then note that it may be necessary to leave a two-hour gap from your medication dose. Ideally however, it's best to take strains such as Lactobacillus acidophilus/helveticus Rosell-52, Lactobacillus rhamnosus Rosell-11 and Bifidobacterium lactis Lafti B94 which can be taken at the same time as your medicine.

    How do probiotics help with antibiotics?

    When the correct strains are taken, probiotics can support your gut health* whilst on the antibiotic medication4. Keeping friendly bacteria populations well supported can help with digestive health* when taking antibiotics. It’s best to start taking For Those On Antibiotics right away at the start of your course, but don’t worry if you miss a couple of days at the beginning, just continue until the pack is complete. Many people like to continue taking probiotics once they have finished their course of medication, to maintain their support of the gut microbiome.


    1. Nagulesapillai V. Detection and Quantification of Strain Specific Probiotics in Clinical Fecal Samples of Healthy Adults on Antibiotic Treatment by Quantitative PCR. Poster presentation. 2015;1(1).
    2. Maydannik V. et al. ‘Efficiency and safety of Lacidofil in children with antibiotic-associated diarrhoea caused by Clostridium difficile.’ Pediatrics, Obstetrics & Gynaecology. 2010;2(3):53-57.
    3. Chernyshov P v. Randomized, placebo-controlled trial on clinical and immunologic effects of probiotic containing Lactobacillus rhamnosus R0011 and L. helveticus R0052 in infants with atopic dermatitis. Published online 2009. doi:10.3109/08910600903444234
    4. Evans M, Salewski RP, Christman MC, Girard SA, Tompkins TA. Effectiveness of Lactobacillus helveticus and Lactobacillus rhamnosus for the management of antibiotic-associated diarrhoea in healthy adults: A randomised, double-blind, placebo-controlled trial. British Journal of Nutrition. 2016;116(1):94-103.

  • Ingredients

    Ingredients For Those On Antibiotics supplement fact panel

    Potato starch; hydroxypropyl methylcellulose (vegetarian capsule); Probiotic blend: Lactobacillus rhamnosus Rosell-11, Bifidobacterium lactis Lafti B94, Lactobacillus acidophilus/helveticus Rosell-52; vegetable magnesium stearate; ascorbic acid (for freshness)

    Each capsule guarantees 4.5 billion live cultures. Guaranteed until the date of expiry.


    • Vegetarian
    • Vegan
    • Dairy free
    • Gluten free
    • Yeast free
    • GMO free
    • Suitable during pregnancy
    • Suitable during breastfeeding
    • Free from artificial flavorings, colorings and preservatives
    • No chemicals or parabens
    • Sugar free

    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 Lactobacillus rhamnosus strain in For Those On Antibiotics may therefore now also be known as Lacticaseibacillus rhamnosus Rosell-11.

  • Help & Advice

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  • Delivery & Returns

    USA Shipping

    Coronavirus Update

    We ship all USA orders from our warehouse in Hampshire in the UK. Due to the ongoing global pandemic many US, European and Worldwide postal routes are seeing increased transit times. Delivery times provided on this site are therefore a guide and not a guarantee. Express Services largely remain unaffected however these routes are typically subject to local tax and duties at customs.

    USA standard shipping: $4.99

    International postal order - typically deatched and delivered within 5-10 working days.
    Free standard shipping on orders over $100.

    USA express shipping: $6.99

    We use DHL and orders are typically dispatched and delivered within 2-5 working days.



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    Worldwide Delivery

    • We deliver to more than 50 countries.
    • Shipping is charged at cost - please note that duties may apply.
    • Please allow 3-7 working days for delivery within Europe and 5-12 days to all other destinations. Includes order tracking.  
    • If you are located within the United Kingdom or Europe, we recommended switching to our UK website.
    • International deliveries might currently take a little longer due to the global coronavirus situation. Please refer to the webpage of our international delivery provider DHL to confirm the number of days it takes to receive your order and whether they currently ship to your country.
    • Most international delivery prices are dependent on the size and weight of your order and where it is being sent. You'll be shown the final price of shipping in the checkout, before payment, once we have your address and order details.
    • Long distance shipping and short-term exposure to high temperatures will not compromise the viability of our products. Customers living in very hot countries should store the products out of direct sunlight and refrigerate if the option is available.

    For more details regarding international orders, currency conversion and applicable tax for orders outside the USA, please take a look at our delivery FAQ.