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Constipation, diarrhea, gut dysbiosis affect 35% of GLP-1 users. These rebuild your microbiome.
35% of GLP-1 users report persistent GI symptoms (constipation, diarrhea, bloating) beyond week 6. Microbiome dysbiosis is the underlying driver in most cases.
Beyond acute nausea, GLP-1s alter the gut microbiome long-term. Slowed transit + reduced food variety + reduced fiber intake = less microbial diversity. Restoring this requires targeted probiotics + sustained fiber intake. Most patients neglect this until chronic GI issues develop.
GLP-1 use shifts gut bacterial populations — Firmicutes decline, Bacteroidetes increase. This affects bile acid metabolism, short-chain fatty acid production, and inflammation markers. Specific probiotic strains (Akkermansia, Lactobacillus reuteri, Bifidobacterium longum) restore lost populations.
When to seek medical advice (not OTC)
Consult prescriber for: blood in stool, unintentional weight loss >5% (beyond intended), severe abdominal pain, persistent diarrhea >7 days, alternating diarrhea/constipation patterns. May indicate gastroparesis or other GI complication beyond microbiome.
Seed
24 clinically-studied probiotic strains + prebiotic. Includes Akkermansia muciniphila — specifically depleted by GLP-1. 2-capsule daily dose.
Culturelle
Lactobacillus rhamnosus GG (LGG) — the most-studied probiotic strain. Widely available, affordable, evidence-based for diarrhea + IBS.
Metamucil
Soluble psyllium fiber. Treats constipation (most common GLP-1 GI complaint) AND feeds beneficial bacteria. 5g per dose.
Miralax
Osmotic laxative for stubborn constipation. Different mechanism from psyllium (water retention vs bulk fiber). Use when fiber alone insufficient.
IBgard
Enteric-coated peppermint oil. Targets bloating + cramping from delayed gastric transit. Different mechanism than antacids.
Slowed gastric emptying + reduced fiber intake (most patients drop calories from veggies) + reduced fluid intake. The fix: 30g fiber/day + 64oz water + probiotic. Constipation responds within 1-2 weeks.
Most patients benefit from 6-12 months supplementation while microbiome stabilizes. After that, dietary diversity (fermented foods, varied fiber sources) often sufficient. Maintenance dosing every other day is reasonable long-term.
Seed bundles 24 strains + prebiotic (synbiotic). Culturelle is single-strain (LGG). For broad spectrum, Seed wins. For targeted treatment (LGG for diarrhea), Culturelle wins at lower cost.
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