Protocol · Digestive Health
Antibiotic-Associated Diarrhea Prevention & Treatment Protocol
Probiotics (Saccharomyces boulardii) and Probiotics (Lactobacillus GG) are the core of this stack, with 5 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Antibiotic-Associated Diarrhea Prevention & Treatment.
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
7 supplements · none graded yet · 1 confirmed study
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| Probiotics (Saccharomyces boulardii) | Amount listed: 250–500 mg (5–10 billion CFU) twice daily during antibiotic course and 1 week after | Yeast probiotic not affected by antibiotics; prevents AAD by restoring gut flora and competing with pathogens | Not graded yet | ||
Confirmed studies for Probiotics (Saccharomyces boulardii) (titles as PubMed lists them) | |||||
| Probiotics (Lactobacillus GG) | Amount listed: 10–20 billion CFU daily during antibiotic course and 1 week after | Well-studied bacterial probiotic strain that reduces AAD risk; take 2 hours apart from antibiotic | Not graded yet | ||
Confirmed studies for Probiotics (Lactobacillus GG) (titles as PubMed lists them) | |||||
| Supporting stackListed as additions to the core | |||||
| Multi-Strain Probiotics | Amount listed: 20–50 billion CFU multi-strain daily | Combination probiotics may provide broader protection; multiple strains restore gut diversity | Not graded yet | ||
Confirmed studies for Multi-Strain Probiotics (titles as PubMed lists them) | |||||
| Kefir | Amount listed: 1–2 cups daily during and after antibiotics | Fermented milk drink with diverse probiotic strains; natural source of beneficial bacteria and yeast | Not graded yet | ||
| Prebiotics (Inulin/FOS) | Amount listed: 5–10 g daily (start low to avoid gas) | Feed beneficial bacteria; may help restore gut microbiome after antibiotic disruption | Not graded yet | ||
| L-Glutamine | Amount listed: 5–10 g daily | Supports gut lining integrity; may help maintain intestinal barrier during antibiotic treatment | Not graded yet | ||
| Zinc | Amount listed: 15–30 mg daily during antibiotic course | Supports gut barrier function and immune response; may help reduce diarrhea severity | Not graded yet | ||
Shop the evidence-backed picks
The collection holds the supplements we grade A or B for its theme, in third-party tested products where the catalog has them. It opens in our Fullscript store. You can look through it without signing in; Fullscript asks for a free account to order.
Or shop one supplement
Each opens third-party tested products, matched to the dose above where we can.
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How this protocol works
In plain language
Antibiotic-associated diarrhea (AAD) is a common side effect of antibiotic treatment, occurring in 5-35% of patients. Antibiotics kill not only harmful bacteria but also beneficial gut bacteria, disrupting the normal gut microbiome. This allows opportunistic bacteria to overgrow and causes digestive symptoms. While most AAD is mild and self-limited, it can sometimes lead to more serious infections like Clostridioides difficile (C. diff).
CRITICAL: While most AAD is mild, severe or bloody diarrhea, fever, or symptoms that persist after stopping antibiotics could indicate C. difficile infection, which requires specific antibiotic treatment. Seek medical attention for severe symptoms. Probiotics are for prevention and mild AAD - they don't treat established C. diff infection. If you need antibiotics, don't stop them without consulting your doctor just because of mild diarrhea.
Saccharomyces boulardii* is a yeast probiotic that is not affected by antibiotics (antibiotics only kill bacteria, not yeast). It's one of the best-studied probiotics for AAD prevention. Multiple meta-analyses show it significantly reduces AAD risk.
Lactobacillus GG (LGG)* is a well-studied bacterial probiotic strain. When taken during antibiotic treatment (2 hours apart from the antibiotic dose), it helps maintain beneficial bacteria and reduce AAD risk.
Multi-Strain Probiotics* may provide broader protection by introducing multiple beneficial species to restore gut diversity.
Kefir* is a natural probiotic food containing multiple bacterial and yeast strains. It provides probiotics in a food matrix that may enhance survival.
Prebiotics* are fibers that feed beneficial bacteria. They may help the remaining good bacteria thrive and support microbiome recovery after antibiotics.
L-Glutamine* is the primary fuel for intestinal cells and supports gut barrier integrity.
Zinc* supports gut barrier function and immune response, and may help reduce diarrhea severity.
Expected timeline: Start probiotics at the beginning of antibiotic treatment and continue for at least 1 week after completing antibiotics. Most AAD resolves within a few days of stopping antibiotics. If diarrhea persists beyond 2 weeks after finishing antibiotics, see a doctor.