Antibiotics kill probiotic bacteria if taken together
Oral antibiotics will kill live probiotic organisms if taken at the same time, making the probiotic useless. Spacing them out preserves both.
Continue probiotics during an antibiotic course — they reduce antibiotic-associated diarrhea. Take the probiotic 2-3 hours after the antibiotic dose.
Separate by at least 2-3 hours; continue for 2+ weeks after finishing antibiotics
Antibiotics kill probiotic bacteria if taken together. Continue probiotics during an antibiotic course — they reduce antibiotic-associated diarrhea. Take the probiotic 2-3 hours after the antibiotic dose.
Separate by at least 2-3 hours; continue for 2+ weeks after finishing antibiotics
This interaction is rated “Caution” by Formulate. Oral antibiotics will kill live probiotic organisms if taken at the same time, making the probiotic useless. Spacing them out preserves both.
Studies from our registry that mention antibiotics or probiotics. Each links to the primary source and the other Formulate pages citing it.
Mentions probiotics · 2017
Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children
Goldenberg et al. · Cochrane Database of Systematic Reviews
39 RCTs, 9,955 participants. Probiotics reduced CDAD risk ~60% in moderate-to-high risk populations.
Mentions probiotics · 2014
Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: systematic review and meta-analysis
Ford et al. · American Journal of Gastroenterology
Pooled analysis of 43 RCTs. Probiotics improved global IBS symptoms vs placebo; specific strains (LP299V, B. longum 35624) showed the largest effects.
Mentions probiotics · 2013
Meta-analysis: Lactobacillus GG for treating acute gastroenteritis in children
Szajewska et al. · Alimentary Pharmacology & Therapeutics
LGG reduced diarrhea duration by roughly 25 hours in pediatric gastroenteritis across multiple RCTs.
Mentions probiotics · 2012
Clinical trial: Lactobacillus plantarum 299v (DSM 9843) improves symptoms of irritable bowel syndrome
Ducrotté et al. · World Journal of Gastroenterology
214 patients with moderate-to-severe IBS. LP299V at 10⁹ CFU/day significantly reduced abdominal pain severity and frequency over 4 weeks.
Mentions probiotics · 2010
Systematic review and meta-analysis of Saccharomyces boulardii in adult patients
McFarland · World Journal of Gastroenterology
Meta-analysis of S. boulardii trials across multiple GI conditions. Consistent reductions in diarrheal symptoms including IBS-D.
Mentions probiotics · 2006
Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome
Whorwell et al. · American Journal of Gastroenterology
362 women with IBS. B. infantis 35624 at 1×10⁸ CFU/day significantly reduced abdominal pain, bloating, and bowel dysfunction vs placebo over 4 weeks.
Guide
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Review
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Most probiotic marketing ignores strain specificity. For IBS, three strains have real clinical evidence — and dozens of common ones have none.
Other interactions to know
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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.
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