Why Does SIBO Keep Coming Back After Treatment? — The clinical pattern that defines recurrent SIBO

A patient presents with bloating, postprandial fullness, food sensitivities, and a positive breath test. They are prescribed rifaximin, sometimes with neomycin if methane is dominant. They feel substantially better within two to four weeks. Their breath test normalizes. Three to six months later, the symptoms return. They retreat. The same pattern repeats. By round four or five, the response to treatment is shorter and less complete than it was the first time. By round six, the patient is often more symptomatic than they were before the first treatment. This pattern is so consistent across SIBO patients that it is essentially diagnostic. The clinical literature documents recurrence rates of 30 to 60 percent within nine months of rifaximin treatment, and higher in hydrogen-sulfide-dominant cases. Anecdotal experience among clinicians working with this patient population places the real number higher, because many patients do not return to the prescribing clinician once it becomes clear the treatment cycle is not converging. The standard interpretation of this pattern is that recurrence reflects insufficient motility, anatomical predisposition, antimicrobial resistance, or inadequate treatment duration. Prokinetics are added. Treatment durations are extended. Antimicrobial classes are cycled. The pattern continues. The alternative interpretation, the one this article will develop