Consider Saccharomyces boulardii during antibiotics specifically

What to Do

Take S. boulardii (Florastor, 250-500 mg twice daily) starting with your first antibiotic dose and continuing for 1-2 weeks after the course ends.

Why It Works

S. boulardii is a yeast, not a bacterium, so antibiotics do not kill it. Meta-analyses show it significantly reduces antibiotic-associated diarrhea (RR = 0.47). Unlike bacterial probiotics, it does not compete with native bacterial recolonization because it occupies a different ecological niche. It also has moderate evidence for preventing C. difficile infection.

Tips

• This is the one probiotic with clear evidence for use alongside antibiotics
• Does not require refrigeration in most formulations
• Safe for most adults; consult a physician if immunocompromised
• Can be taken at the same time as antibiotics since they target bacteria, not yeast