Taking Probiotics Alongside Weight Loss Medications

• What are GLP-1 medications?
• Why has Ozempic become so popular?
• Common GI side effects of GLP-1 medications
• The role of the gut microbiome in GI health
• Probiotics for managing GLP-1 medication side effects
• How to use probiotics alongside weight loss medications
• Key takeaway

What are GLP-1 medications?

Weight loss medications, such as Ozempic, Wegovy, and Mounjaro, are a type of drug originally designed to help people with type 2 diabetes manage their blood sugar^1,4. However, they have recently gained attention for their ability to support weight loss.

These medications work by mimicking a natural gut hormone called glucagon-like peptide-1 (GLP-1), which helps control blood sugar levels², slow down digestion, and reduce appetite³. This means people feel fuller for longer and eat less, leading to weight loss.

Why has Ozempic become so popular?

• Highly Effective for Weight Loss – Clinical trials have shown that GLP-1 RAs can lead to significant and sustained weight loss⁵, making them a breakthrough in obesity treatment.
• Appetite Suppression – These drugs reduce hunger and cravings⁶, helping individuals consume fewer calories.
• Celebrity & Media Attention – Widespread media coverage and endorsements from high-profile figures have contributed to their popularity.
• Obesity as a Medical Condition – More healthcare professionals now recognize obesity as a chronic disease requiring medical intervention rather than just lifestyle changes.

Common GI side effects of GLP-1 medications

Despite their effectiveness, GLP-1 RAs often cause gastrointestinal side effects^7,8, especially during the initial weeks of treatment as the body adjusts:

• Nausea & Vomiting – Due to slower stomach emptying, food stays in the stomach longer, leading to feelings of fullness and nausea.
• Diarrhea – Increased gut motility and changes in digestion may lead to loose stools.
• Constipation – Slower intestinal movement can result in constipation for some individuals⁹.
• Abdominal Pain & Bloating – Changes in digestion and gut microbiota can cause discomfort and bloating.

These side effects can impact adherence to the medication, leading some people to discontinue treatment¹⁰. However, probiotics may offer a way to support the gut and alleviate these symptoms, improving tolerance to GLP-1 RAs.

The role of the gut microbiome in GI health

The gut microbiome, comprising trillions of microorganisms, plays a crucial role in digestion, nutrient absorption, and immune function^11,12. Disruptions in this microbial balance can lead to GI symptoms.

Probiotics - live beneficial bacteria - can help restore and maintain a healthy gut microbiome. They exert positive effects by:

• Enhancing Digestive Function: Aiding in the breakdown of food substances.
• Modulating Immune Responses: Reducing inflammation and promoting immune tolerance.
• Inhibiting Pathogenic Bacteria: Competing with harmful microbes for resources and adhesion sites.

Probiotics for managing GLP-1 medication side effects

Research indicates that specific probiotic strains may alleviate GI side effects associated with GLP-1 RAs:

• Diarrhea: Saccharomyces boulardii has demonstrated efficacy in reducing antibiotic-associated diarrhea¹³ and may help manage diarrhea induced by GLP-1 RAs. 
• Constipation: Bifidobacterium lactis BB-12® has been shown to improve bowel regularity and stool consistency¹⁴, potentially counteracting constipation. 
• Abdominal Pain and Bloating: Lactobacillus acidophilus NCFM® and Bifidobacterium lactis Bi-07® have been associated with reductions in abdominal discomfort and bloating in individuals with irritable bowel syndrome (IBS)¹⁵. 

Health Professionals can read about these probiotic strains on our Probiotic Database.

How to use probiotics alongside weight loss medications

To maximise benefits and minimise potential interactions:

• Consult Healthcare Providers: Before starting probiotics, discuss with a healthcare professional, especially if you have underlying health conditions or are on multiple medications.
• Select Appropriate Strains: Choose probiotics with strains supported by clinical evidence for specific symptoms.
• Monitor for Side Effects: While probiotics are generally safe, monitor for any adverse reactions and report them to your healthcare provider.

Key takeaway

Specific probiotic strains such as Saccharomyces boulardii and Bifidobacterium lactis BB-12® can offer a supportive approach to managing GI side effects associated with GLP-1 receptor agonists. Ongoing research continues to elucidate the full extent of these benefits, underscoring the importance of personalised medical advice in treatment planning.

You may also wish to read our related articles:

Probiotics for Depression

Probiotics and PCOS

Probiotics and Antibiotic-Associated Diarrhoea

References

1. MacDonald, P. E. et al. The multiple actions of GLP-1 on the process of glucose-stimulated insulin secretion. Diabetes 51, S434–442 (2002).
2. Bu, T. et al. Glucagon-like peptide-1: New regulator in lipid metabolism. Diab Metab. J. 48, 354–372 (2024).
3. Andreasen, C. R., Andersen, A., Knop, F. K. & Vilsbøll, T. How glucagon-like peptide 1 receptor agonists work. Endocr. Connect 10, R200–r212 (2021).
4. Blevins, T. et al. DURATION-5: Exenatide once weekly resulted in greater improvements in glycemic control compared with exenatide twice daily in patients with type 2 diabetes. J. Clin. Endocrinol. Metab. 96, 1301–1310 (2011).
5. O’Neil, P. M. et al. Efficacy and safety of semaglutide compared with liraglutide and placebo for weight loss in patients with obesity: a randomised, double-blind, placebo and active controlled, dose-ranging, phase 2 trial. Lancet 392, 637–649 (2018).
6. Moon, S. et al. Efficacy and safety of the new appetite suppressant, liraglutide: A meta-analysis of randomized controlled trials. Endocrinol. Metab. (Seoul.) 36, 647–660 (2021).
7. Ghusn W, Hurtado M (2024) Glucagon-like Receptor-1 agonists for obesity: Weight loss outcomes, tolerability, side effects, and risks. Obesity Pillars, 12: 100127
8. Bettge K, Kahle M, Abd El Aziz MS, et al. Occurrence of nausea, vomiting and diarrhoea reported as adverse events in clinical trials studying glucagon-like peptide-1 receptor agonists: a systematic analysis of published clinical trials. Diabetes Obes Metab. 2017;19(3):336–347.
9. Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity. N Engl J Med. 2021;384(11):989.
10. Sikirica MV, Martin AA, Wood R, et al. Reasons for discontinuation of GLP1 receptor agonists: data from a real-world cross-sectional survey of physicians and their patients with type 2 diabetes. Diabetes Metab Syndr Obes. 2017;10:403–412.
11. Montalban-Arques A et al (2015) Selective Manipulation of the Gut Microbiota Improves Immune Status in Vertebrates, Frontiers in Immunology. Oct 9;6:512. doi: 10.3389/fimmu.2015.00512. eCollection 2015.
12. Fang et al (2000) Modulation of humoral immune response through probiotic intake. FEMS Immunol Med Microbiol. 2000 Sep;29 (1):47-52.
13. McFarland L.V., (2010), ‘Systematic review and meta-analysis of Saccharomyces boulardii in adult patients’. World Journal of Gastroenterology, 16(18):2202–2222.
14. Eskesen D, Jespersen L, Michelsen B, Whorwell PJ, Müller-Lissner S, Morberg CM. Effect of the probiotic strain Bifidobacterium animalis subsp. lactis, BB-12®, on defecation frequency in healthy subjects with low defecation frequency and abdominal discomfort: A randomised, double-blind, placebo-controlled, parallel-group trial. Br J Nutr. 2015;114(10):1638-1646. doi:10.1017/S0007114515003347
15. Magro, D.O., et al., (2014). ‘Effect of yogurt containing polydextrose, Lactobacillus acidophilus NCFM and Bifidobacterium lactis HN019: a randomized, double-blind, controlled study in chronic constipation’. Nutrition Journal, 13:75.