Protocol · Gastrointestinal
Small Intestinal Bacterial Overgrowth (SIBO) Protocol
Berberine and Oregano Oil (Carvacrol) are the core of this stack, with 3 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Small Intestinal Bacterial Overgrowth (SIBO).
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
5 supplements · none graded yet
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| Berberine | Amount listed: 500 mg three times daily | Natural antimicrobial that targets SIBO bacteria; comparable efficacy to rifaximin in studies | Not graded yet | ||
| Oregano Oil (Carvacrol) | Amount listed: 200 mg enteric-coated twice daily | Antimicrobial essential oil that disrupts bacterial cell membranes | Not graded yet | ||
| Supporting stackListed as additions to the core | |||||
| Digestive Enzymes | Amount listed: Full-spectrum enzyme with meals | Improves macronutrient digestion, reducing substrate for bacterial fermentation | Not graded yet | ||
| Ginger | Amount listed: 1,000 mg daily | Prokinetic that enhances gastric emptying and migrating motor complex | Not graded yet | ||
| Partially Hydrolyzed Guar Gum (PHGG) | Amount listed: 5 g daily (post-treatment phase) | Prebiotic fiber that supports beneficial bacteria after antimicrobial treatment | 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
SIBO occurs when bacteria that normally live in the colon overgrow into the small intestine, causing bloating, gas, diarrhea, and nutrient malabsorption. Treatment involves reducing bacterial overgrowth and restoring normal gut motility.
- Berberine is a plant compound with natural antimicrobial properties. A study showed herbal antimicrobials (including berberine) were as effective as rifaximin, the standard antibiotic for SIBO, with a 46% response rate.
- Oregano oil contains carvacrol and thymol, which have antibacterial effects against SIBO-associated organisms. Use enteric-coated capsules to ensure delivery to the small intestine.
- Digestive enzymes help break down food more completely, leaving less fuel for bacteria to ferment.
- Ginger is a natural prokinetic—it helps the migrating motor complex (the intestine's cleaning wave) work properly. Poor motility is a major cause of SIBO recurrence.
- PHGG is a well-tolerated prebiotic fiber used AFTER antimicrobial treatment to support healthy bacterial recolonization.
Important: SIBO often has underlying causes (low stomach acid, adhesions, diabetes, hypothyroidism) that must be addressed to prevent recurrence.
Expected timeline: Herbal antimicrobials are typically used for 4-6 weeks. Symptom improvement often begins within 2 weeks. Retest breath test after treatment.