Fiber supplementation for GLP-1 constipation — need advice

Answering the narrow version, because the broad one does not have a single answer. The mechanism is slowed transit plus reduced intake, and that combination determines which interventions work. Less food means less bulk, slower motility means more water reabsorbed, and the result is a smaller, drier, slower stool. Insoluble fiber adds bulk to a system that is already moving slowly, which is why it frequently makes things worse. Soluble fiber holds water and is the better first choice, and an osmotic agent works with the mechanism rather than against it.

PurityPaulOR said:

The mechanism is slowed transit plus reduced intake, and that combination determines which interventions work.

Heartburn management on constipation: Pepcid (famotidine) 20mg has been my savior. The delayed gastric emptying means stomach acid just sits there.

Don't ignore persistent heartburn — chronic acid exposure can damage your esophagus. If OTC remedies aren't cutting it after 2 weeks, see your doctor for something stronger. You shouldn't suffer through this.

Dr.SurgeonPGH said:

I added fiber, made it noticeably worse, and only later worked out that I had added the bulk without adding the water.

Same position here, arrived at the long way round. The escalation order that reflects the mechanism: water and salt first, then soluble fiber, then magnesium or an osmotic agent, then a stimulant only briefly and only if the osmotic has failed. Stimulants first is the commonest error and the one most likely to end in a cycle of dependence.

From the other side of the consultation, briefly.

Gastroparesis symptoms with constipation: the delayed gastric emptying from GLP-1 agonists can cause early satiety, bloating, and feeling "full" for hours after a small meal.

Tips: eat your protein FIRST (most important macro), then vegetables, then carbs last. Chew thoroughly — 20-30 chews per bite isn't excessive. Avoid carbonated beverages with meals. If symptoms are severe, your doctor may recommend a gastric emptying study.