Product Review

Note: VSL#3 was discontinued in Canada. However, there is a new product available in Canada, Visbiome®, which contains the same active ingredients. Click here for more information about Visbiome®.


Many individuals take probiotics to reduce symptoms from gastrointestinal (GI) disorders or to improve their overall intestinal health. Since most people view probiotics as safe, natural, and effective, they are popular products. However, not all probiotics are equal.

The World Health Organization defines probiotics as “live microorganisms which when administered in adequate amounts confer a health benefit on the host.” They include bacteria as well as yeasts. Probiotics work in many possible ways, including:

  • lining the surface of the gastrointestinal tract and stopping harmful organisms from reaching it (competitive exclusion),
  • strengthening the tissue of the bowel wall,
  • acting as antibiotics against other bacteria, and
  • regulating the responses of the immune system, both at the level of the bowel wall and the body as a whole.

As natural health products rather than prescription medications, probiotics aren’t required to complete the same rigorous testing as pharmaceutical medications, so it can be difficult to know what you are getting with many products. Due to labelling regulations (or lack-thereof), companies can claim whatever they want on the bottle, but it doesn’t mean the information is true. That is why it’s important to choose a product with proven results.

Evidence shows that VSL#3®, which is a probiotic blend of live, freeze-dried lactic acid bacteria and bifidobateria is beneficial for individuals with ulcerative colitis. There are 450 billion bacteria in each dose, consisting of a set ratio of the following eight probiotics: Bifidobacterium breve, Bifidobacterium longum, Bifidobacterium infantis, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus bulgaricus, Streptococcus thermophilus.

Available in unflavoured or lemon flavoured, each VSL#3® dose comes in a sachet that you add to a non-carbonated, cold beverage of your choice such as water, juice, or milk. If you are on antibiotics while taking VSL#3®, the product’s effectiveness will be reduced because antibiotics often destroy good bacteria along with the pathogen they are prescribed to fight. VSL#3® may cause mild bloating in new users, as the body adjusts to the change in colonic microbiota. However, there are no other known interactions or side effects. These strains of probiotics are frequently occurring species in the human gut and are generally safe.

Studies conducted with VSL#3® have shown great promise in the efficacy of this probiotic combination for inducing and maintaining remission in those with ulcerative colitis. One study, conducted on children with this disease, found that after 4 weeks of steroid therapy along with either VSL#3® or placebo, 92.8% in the VSL#3® group achieved remission, compared with only 36.4% in the placebo group. To maintain the remission, the researchers gave the children 5-ASA along with either VSL#3® or placebo. They then monitored the children over the next 12 months, and found that 73.3% of those who had 5-ASA and placebo experienced a relapse, compared with only 21.4% of those who were taking 5-ASA and VSL#3®. This study also reported no biochemical or clinical adverse effects from VSL#3®.1

Many probiotic formulas contain beneficial bacteria, but due to differences in preparation in some products, these bacteria die off from varying conditions throughout the GI tract and never make it to the place they need to be. Another study2 shows that probiotics from VSL#3® do make it to the colon, which is the area they need to reach to be effective.

VSL#3® does not require a prescription, but you should talk to a physician before you decide to take it, to ensure it is right for you and that it will be a beneficial treatment for your disease.


Natural health products don’t require rigorous testing; however, Health Canada does have a system in place for acknowledging the products that use research to prove their efficacy, safety, and quality. These products will have an 8-digit number on their label called a Natural Product Number (NPN). You can use a product’s NPN to search the Licensed Natural Health Products Database3 online, where you can find information about the product, such as licensing, dosing, ingredients, recommended uses, warnings, and more. The NPN for VSL#3 is 80042116.

Read about one man’s experience with VSL#3®.

First published in the Inside Tract® newsletter issue 193 – 2015
1. Miele E et al. Effect of a Probiotic Preparation (VSL#3) on Induction and Maintenance of Remission in Children With Ulcerative Colitis. American Journal of Gastroenterology. 2009;104:437-43.
2. Bibiloni R et al. VSL#3 Probiotic-Mixture Induces Remission in Patients with Active Ulcerative Colitis. American Journal of Gastroenterology. 2005;100:1539-46.
3. Health Canada. Search Licensed Natural Health Products. Available at: http://webprod5.hc-sc.gc.ca/lnhpd-bdpsnh/index-eng.jsp. Accessed 2015-02-04.