Best Laxatives for GLP-1 Constipation — Ozempic, Wegovy, Zepbound (2026)

“Unflavored powder dissolves completely in any liquid — truly tasteless, which is its biggest advantage over flavored competitors.”

PEG 3350 is the closest thing to a purpose-built answer for GLP-1 constipation. The drug class slows gastric emptying and intestinal transit; an osmotic laxative doesn't fight that — it works at the far end, holding water in the colon so whatever arrives there stays soft and passable. Nothing is added to your stomach volume (a real consideration when you already feel full for hours), nothing ferments into gas, and nothing stimulates. It's the AGA/ACG first-line recommendation for chronic constipation, it's built for daily use, and since GLP-1 constipation lasts as long as the prescription does, a daily-safe option is exactly what the situation calls for. Expect 1-3 days to onset and mix each dose with a full glass of water — hydration is doing half the work here.

“Small brown tablets with a faint herbal smell. The gummy form tastes like a slightly earthy mixed berry — better than expected for a laxative, but not something you'd eat for fun.”

When you're already several days backed up, an osmotic starting today is cold comfort. Senna triggers colon contractions in 6-12 hours — bedtime dose, morning result — and it's the gentler of the two major stimulant options. On a GLP-1, the sensible pattern is senna as the occasional circuit-breaker while daily MiraLAX prevents the next episode, not senna as the nightly plan. One honest caution: stimulant cramping lands on top of whatever GI symptoms the medication is already giving you, so start with the lowest dose.

“Truly tasteless and dissolves completely — you genuinely cannot tell it's in your coffee or water. No texture, no grit, no aftertaste. The tradeoff is less fiber per serving than Metamucil.”

Eating dramatically less — the entire point of the medication — usually means eating dramatically less fiber, so a supplement makes sense. But GLP-1 users have a specific problem with the classic choice: psyllium adds bulk and can ferment into gas, and both land badly on a stomach that empties slowly and already feels full. Wheat dextrin is the workaround — it dissolves completely into any liquid with no thickening, no grit, and comparatively little gas. Its constipation evidence is weaker than psyllium's, which is why it isn't ranked higher, but it's the fiber most likely to be tolerated alongside GLP-1 fullness.

“The orange flavor is strong and the psyllium gives it a thick, slightly gritty texture that takes getting used to. Must drink immediately after mixing — it gels fast and becomes undrinkable.”

Psyllium has the best constipation evidence of any fiber, and if your GLP-1 constipation is fundamentally a fiber-gap problem, it's the most effective fix. The caution is mechanical: psyllium gels and adds bulk, which a slowed stomach registers as more fullness, and early-course GLP-1 users battling nausea often can't tolerate it. Our advice: don't start here. If MiraLAX plus gentle fiber isn't enough after a couple of weeks, introduce psyllium at half-dose with plenty of water and build up slowly — and if it makes the fullness worse, drop back to wheat dextrin without guilt.

“Thick, chalky white liquid that coats your mouth. The unflavored original tastes exactly like liquid chalk. The mint and cherry flavors mask it somewhat, but the texture is the real challenge — think melted ice cream consistency but chalky.”

For same-day relief without a stimulant, magnesium hydroxide pulls water into the gut within 30 minutes to 6 hours. It has a real place as an occasional alternative to senna — some people simply tolerate an osmotic flush better than stimulant contractions. Two limits keep it at #5: it's strictly an occasional tool (chronic magnesium dosing is how the rare hypermagnesemia cases happen), and it's off the table entirely for anyone with kidney disease — worth taking seriously, since some GLP-1 users have diabetes-related kidney impairment. If that's you, this option needs a doctor's OK first, not a shelf grab.