Prescription Options

Prescription Prokinetics for GP Discussion

If natural prokinetics + herbal treatment doesn't resolve SIBO, these are worth discussing with your GP.

Low-Dose Erythromycin (50mg at bedtime)

• What it does: Motilin receptor agonist — motilin is the hormone that directly triggers the MMC. At 50mg, this is purely a motility agent, NOT functioning as an antibiotic (antibiotic dose is 250-500mg).
• Dose: 50mg at bedtime. May need compounding pharmacy to reach this dose — standard tablets are typically 250mg+.
• Duration: Long-term maintenance, taken ongoing after active SIBO treatment.
• Effectiveness: One of the most potent prokinetics available. Commonly prescribed by SIBO specialists (Dr. Pimentel at Cedars-Sinai, Dr. Siebecker).
• Availability: Your GP should be able to prescribe it. Raise the sub-antibiotic prokinetic use specifically — many GPs won't think of erythromycin as a prokinetic unless you mention it.

Prucalopride (Resolor)

• What it does: 5-HT4 receptor agonist — stimulates serotonin receptors in the gut that drive intestinal contractions.
• Dose: 0.5-1mg at bedtime. Standard Resolor tablets come in 1mg and 2mg in AU.
• Duration: Ongoing maintenance after active SIBO treatment.
• Effectiveness: Strong evidence for promoting intestinal contractions. Particularly useful if constipation is part of the picture.
• Availability: PBS-listed in Australia. Originally approved for chronic constipation, used off-label for SIBO prevention.

Low Dose Naltrexone (LDN) — Already Taking

• 2.5mg at bedtime (diarrhoea types) or 5mg (constipation types)
• Briefly blocks opioid receptors → endorphin upregulation → anti-inflammatory + motility effects
• Can be combined with other prokinetics (different mechanism)

Both prescription prokinetics are long-term maintenance medications — they don't cure SIBO, they prevent recurrence by keeping the MMC running properly.

Elemental Diet (Reserve Option)

A liquid-only formula of pre-digested nutrients consumed for 2-3 weeks. Nutrients absorb in the upper small intestine before bacteria can feed on them, starving the overgrowth.

Evidence

• 80% breath test normalisation rate in one 14-day course (vs ~50-65% for antibiotics)
• Lowers gas levels by ~70 ppm per round on average
• Effective for all SIBO types (hydrogen, methane, hydrogen sulfide)
• One round of elemental diet can eliminate or greatly reduce the need for multiple rounds of antibiotics

Practical Considerations

• Cannot combine with antibiotics or herbal antimicrobials (diet starves bacteria into dormancy; antimicrobials need active replicating bacteria)
• Must be followed by prokinetics and gradual food reintroduction
• Mentally challenging — no solid food for 2-3 weeks
• Costly (commercial formulas)
• Dr. Siebecker has a homemade recipe, though commercial formulas are more reliable

Side Effects

• Die-off symptoms (same as any SIBO treatment)
• Reduced motility (no food stimulating natural contractions)
• Potential fungal overgrowth (prophylactic anti-fungals sometimes prescribed alongside)

When to Consider

• After herbal antimicrobials have been tried and haven't fully cleared SIBO
• If breath test remains elevated despite completing Phase 1-3
• If symptoms are severe enough to justify the difficulty
• As a first-line treatment for very high breath test results (some practitioners prefer it over antibiotics for severe cases)

Available in Australia

Commercial elemental diet formulas can be sourced through integrative practitioners. Some brands available online. Discuss with your treating practitioner for specific product recommendations and supervision.