The ingredients in Holigos® IBS are generally recognized as safe (GRAS) and have been certified as safe

Holigos® IBS contains two oligosaccharides naturally found in human milk and both are certified as safe by the European Food Safety Authority (EFSA) and accorded GRAS status by the US Food and Drug Administration (FDA). Both have been approved for use in infant formula and medical foods.

Holigos® IBS is very well tolerated by infants, children and adults, including IBS patients

Holigos® has been evaluated in several randomized, placebo controlled clinical trials1,2,3,4 and has shown very good tolerance in infants, children and adults (both healthy and IBS patients). In total, over 2000 people have tested Holigos® during development.

There is no difference in reported adverse events between Holigos® IBS and placebo

The number of adverse events (AEs) reported in the clinical trials were similar for participants taking Holigos® or placebo. The most commonly reported AEs were local reactions in the gut, such as abdominal pain, distension and flatulence. All AEs were considered to be of mild or moderate severity. No serious adverse events attributed to Holigos® have been reported.  Trial discontinuation rates were infrequent and similar between those taking Holigos® and placebo.

Food allergies and intolerances

  • Soy, peanut, egg or gluten: Holigos® IBS does not contain soy, peanut, egg or gluten 
  • Lactose: Holigos® IBS is suitable for consumption by people who are lactose intolerant. Each daily dose of Holigos® IBS contains less than 0.2g of lactose which is generally too low to trigger symptoms of lactose intolerance. Further, Holigos® IBS promotes the growth of beneficial bacteria which consume lactose.
  • Milk protein: Holigos® IBS may contain traces of milk protein

Holigos® IBS may be used during pregnancy and lactation at clinical discretion

Holigos® IBS has not been tested in pregnant or lactating women. However, Holigos® IBS contains glycans which are found in high concentrations in mother’s milk and are beneficial to the nursing baby. Therefore, safety and tolerance issues are not expected but the choice to administer Holigos® IBS during pregnancy or to nursing mothers is at the clinical discretion of the medical professional.

No potential drug interactions have been identified from any source including clinical trials

No interactions trials have been conducted in people who are taking Holigos® IBS and other medicines. However, no potential drug interactions have been identified from any source including clinical trials.

Read more about clinical evidence


1 Elison, E., et al., Oral supplementation of healthy adults with 2'-O-fucosyllactose and lacto-N-neotetraose is well tolerated and shifts the intestinal microbiota. Br J Nutr, 2016: p. 1-13. 2 Puccio, G., et al., Effects of infant formula with human milk oligosaccharides on growth and morbidity: a randomized multicenter trial. Journal of Pediatric Gastroenterology and Nutrition, 2017. 64(4): p. 624. 3 Storm, HM, et al., 2′-Fucosyllactose Is Well Tolerated in a 100% Whey, Partially Hydrolyzed Infant Formula With Bifidobacterium lactis: A Randomized Controlled Trial, Global Pediatric Health, 2019, Volume 6: 1–10.  Iribarren, C., et al, The Effects of Human Milk Oligosaccharides on Bifidobacteria and gastrointestinal symptoms in IBS: A parallel, Double Blind, Randomized, Placebo-controlled Trial, DDW2019.