Clinical Trial: Multi-Strain Probiotic Improves Bile Acid Profile, Microbiome, and Metabolomic Parameters in Patients With History of Bile Acid Malabsorption-A Randomized, Controlled Trial.

Identify candidates for bile acid diarrhea (BAD) among patients with chronic diarrhea by RISK FACTORS, prior terminal ileal resection, cholecystectomy, or abdominal radiotherapy (strong recommendation, very low certainty); do NOT rely on symptom presentation alone to identify BAD (conditional, very low certainty). Diagnose by testing rather than by treating. In chronic diarrhea, IBS-D, and functional diarrhea, test with SeHCAT where available (conditional, very low certainty) or with a 7-alpha-hydroxy-4-cholesten-3-one (C4) assay (conditional, very low certainty). In small-intestinal Crohn's disease without active inflammation and persistent diarrhea, the guideline recommends SeHCAT specifically (conditional, very low certainty); the C4-assay recommendation is confined to the chronic diarrhea, IBS-D, and functional diarrhea population and is not extended to this Crohn's group. The guideline explicitly SUGGESTS AGAINST empiric bile acid sequestrant therapy in preference to SeHCAT testing (conditional, very low certainty), an empiric trial is a fallback where testing is unavailable, not a co-equal diagnostic strategy. Treat remediable contributing causes (active Crohn's disease, microscopic colitis, SIBO) alongside BAD (conditional, very low certainty). For induction, use cholestyramine over no treatment (conditional, very low certainty) and cholestyramine over other sequestrants as INITIAL therapy (conditional, very low certainty), switching to an alternate sequestrant when cholestyramine is poorly tolerated (conditional, low certainty). Dose cholestyramine from 2-4 g/day titrated to response (range up to 4-24 g/day); colestipol from 1 g twice daily increasing by 1 g/day every other day; colesevelam 625 mg two tablets three times daily (3.75 g/day). Gradual daily dose titration should be used to minimize side effects (good practice statement). SUGGEST AGAINST sequestrants in patients with extensive ileal Crohn's disease or ileal resection (historically >100 cm) because of steatorrhea risk (conditional, very low certainty), evaluate case by case; use alternative antidiarrheal agents in patients who cannot tolerate sequestrants (conditional, very low certainty). For maintenance, try intermittent, on-demand dosing after initial response (conditional, very low certainty) and use the lowest dose needed to control symptoms (good practice statement). Review concurrent medications (good practice statement): per Health Canada labeling, take other drugs at least 1 hour before or 4-6 hours after the sequestrant (a 3-hour window may suffice based on gastric-emptying data); interacting drugs include thyroid preparations, warfarin, and digoxin, with colesevelam having lower interaction potential. Re-investigate diagnostically if symptoms worsen despite stable sequestrant therapy (good practice statement). The guideline makes NO RECOMMENDATION for or against measuring fat-soluble vitamin levels at baseline or annually (very low certainty); product labels advise supplementing vitamins A, D and K only if a deficiency occurs. Note that 16 of the 17 recommendations are conditional and most rest on very low certainty evidence.