One week flat

7 sachets


(ex. tax)
4.2/5 (79 reviews) Read the product reviews

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Suitable for



Gluten free

Gluten free

During pregnancy

During pregnancy

During breastfeeding

During breastfeeding


OptiBac Probiotics 'One week flat' is an easy-to-take 7-day course of live cultures and prebiotics, containing 5 billion friendly bacteria and 0.3g prebiotic FOS fibres per sachet.

This 4-strain live cultures combination, including the world renowned Lactobacillus acidophilus Rosell-52, supports digestive health, including occasional bloating*. 

one week flat press

Probiotic strains & ingredients

  • Lactococcus lactis Rosell-1058
  • Lactobacillus casei Rosell-215
  • Lactobacillus acidophilus Rosell-52
  • Bifidobacterium bifidum Rosell-71
  • Product description

  • How to use

  • Ingredients

  • Help & advice

  • Reviews

  • Product description

    Friendly bacteria expert Jen (Complementary Therapy BSc Hons) explains OptiBac 'One week flat'

    Who is 'OptiBac Probiotics One week flat' for​?

    For those with occasional bloating, especially designed to be taken for one week. 

    Key benefits

    • Each sachet provides 5 billion live cultures + 0.3g Fructooligosaccharides (FOS) - the billions count is guaranteed until end of expiry.
    • Contains 4 high quality friendly bacteria strains from the world's leading probiotic laboratories, all scientifically proven to survive stomach acidity and reach the gut alive. 
    • Complements your natural gut bacteria.
    • Includes one of the world's best probiotic strains, Lactobacillus acidophilus Rosell-52, which has been shown to support digestion and ease the discomfort associated with occasional bloating*. 
    • Easy to take on the go – no refrigeration required.
    • Suitable for all from 4 years, including pregnant and breastfeeding women, vegetarians, and coeliacs.
    • Free from artificial flavourings or colourings often found in other food & drinks containing probiotics.
    • Take for 7 consecutive days (1 sachet per day) or as professionally directed.
    • Can be taken once a month, or as frequently as desired.
    • Available to order in two pack sizes of 7 or 28 sachets.
    • From the UK’s most trusted & recommended brand of friendly bacteria supplements. As determined in an independent survey of 1000 British women+

    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 

    Natural food supplement suitable for adults and children (from 4 year onwards) with the following recommendations:

    • Take 1 sachet daily with breakfast for a 7-day course, or as professionally directed.
    • Pour an inch of water into a tall glass, leaving plenty of room for swirling.
    • Shake the sachet well before gently sprinkling the powder into the glass.
    • Vigorously swirl the water around in the glass making sure the powder is dissolved.
    • Drink, wait and enjoy the benefits.

    We highly recommend you take 'One week flat' for 7 consecutive days. Most consumers take this course once a month. However, it can be taken as often as desired.

    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. The OptiBac Probiotics range will not cause dependency, and may be used on an ongoing basis.


    Like the rest of the OptiBac Probiotics range, 'One week flat' 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.

  • Ingredients

    Ingredients one week flat supplement fact panel

    • Stabiliser: maltodextrin (natural source)
    • Fructooligosaccharides (FOS)
    • Live cultures: Lactococcus lactis Rosell-1058, Lactobacillus casei Rosell-215, Lactobacillus acidophilus Rosell-52 and Bifidobacterium bifidum Rosell-71

    Each sachet guarantees 5 billion good bacteria + 0.3g FOS fibres.

    Suitable for vegetarian and gluten-free diets.

    Following the taxonomic updates by a global team of scientists and published in April 2020, a reclassification has been advised for the L. casei species. The casei strain in the OptiBac Probiotics 'One week flat' product is now also known as Lacticaseibacillus casei Rosell-215.



    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

    • I started taking the 28 course for my wedding and did not think I was very bloated but apparently so. I feel so much more comfortable when using these, my periods are less bloaty and after a big or heavy meal the bloating is also controlled and my trousers fit so much better. Does not taste of anything and I drink lots of water so this product is nice and easy for me. I found it cheaper on Medino website - hence the one less star.

      Emily - 22nd October 2020

    • I decided to try the ‘one Week flat’ probiotic after a few years of painful bloating & after being diagnosed with IBS & a gluten intolerance. I now call these my ‘magic powders’ i can’t praise them enough, my tummy is so much better with no bloating & no painful IBS - fabulous!

      Judith Cound - 4th June 2020

    • I suffer with bloating when it's my time of the month, this has helped massively i've noticed a difference within 3 days of use whilst continuing a healthy diet and regular exercise

      Ellen - 7th June 2019

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