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Side effect · Zepbound

Diarrhea on Zepbound

Diarrhea is one of the top stomach side effects in GLP-1 trials, and high-fat meals are a common trigger people do not expect.

Clinician review pending Updated
On Zepbound
19% to 23%
label rate
On placebo
7%
same trials
Extra vs placebo
up to 16points
attributable to the drug, roughly

Pooled placebo-controlled weight-management trials in the Zepbound label (5 mg, 10 mg and 15 mg).

Diarrhea across GLP-1 medicines

Wegovyplacebo 16%
30.0%
Zepboundplacebo 7%
23.0%
Saxendaplacebo 9%
21.0%
Mounjaroplacebo 9%
17.0%
Trulicityplacebo 7%
13.0%
Victozaplacebo 4%
12.0%
Rybelsusplacebo 4%
10.0%
Ozempicplacebo 2%
9.0%
Highest rate across label doses. Different trials and populations, so compare with care.

Why it happens

GLP-1 medicines change how the gut moves food and fluid. That can speed things up lower in the gut even while the stomach empties more slowly.

Diet changes also play a part. Sugar alcohols in protein bars, large amounts of fat and sudden jumps in fiber can all loosen stools.

When it starts and fades

Diarrhea is most common in the first weeks of treatment and after dose steps. In the trials, stomach side effects were mostly mild to moderate and most frequent during dose escalation.

For many people it settles as the body adjusts. If it persists beyond a few days, or comes with signs of dehydration, contact your prescriber.

What helps

  • Drink extra fluids, and consider an oral rehydration drink if stools are frequent.
  • Limit greasy foods, very spicy dishes and large servings of dairy if they bother you.
  • Check labels for sugar alcohols like sorbitol and maltitol in bars and shakes.
  • Eat smaller, simpler meals until things settle.
  • Add fiber slowly rather than all at once.
  • Keep notes on foods and timing to spot your personal triggers.

Other Zepbound side effects

Nausea25% to 29%Vomiting8% to 13%Constipation11% to 17%Stomach pain9% to 10%Heartburn and indigestion7% to 9%Injection-site reactions6% to 8%Fatigue5% to 7%Hair loss4% to 5%Burping3% to 6%Gas3% to 4%Bloating3% to 4%Dizziness3% to 5%

Common questions

How common is diarrhea on Zepbound?

In the trials behind the label, 19% to 23% of people on Zepbound reported it, vs 7% on placebo.

Why do I get diarrhea on Mounjaro?

Tirzepatide changes how the gut moves food and fluid, and diet changes can add to it. It is a known label side effect and is most common after dose increases.

Can I take anti-diarrhea medicine on a GLP-1?

Ask your prescriber or pharmacist before taking any over-the-counter medicine, so they can check it fits your situation.

Will diarrhea affect how my medicine works?

For injected GLP-1s, the drug is absorbed under the skin, not through the gut. Ongoing diarrhea is still worth reporting because of fluid loss.

Sources

  1. Zepbound prescribing information (FDA label on DailyMed)
  2. SURMOUNT-1 trial publication

Clinician review pending. Drafted from primary sources and waiting for sign-off by a licensed clinician (MD, DO or PharmD) before launch. Every number is checked against its source. Drug facts are re-checked quarterly, prices monthly and whenever a label changes. How we review · Report an error