Side effects guide

Mazdutide Side Effects

GLP-1 / glucagon dual agonist

In the mazdutide trials, the most common adverse events were gastrointestinal: nausea, diarrhea, and vomiting, along with reduced appetite. They were generally mild to moderate and tended to track the dose, showing up most during escalation and at the higher 9 mg arm.[1][2]

Reviewed for accuracy · Last reviewed July 8, 2026

Reported side effects

COMMONNausea · Diarrhea · Vomiting · Reduced appetite
LESS COMMONConstipation · Injection-site irritation · Upper respiratory infection

Because mazdutide is investigational outside China, its longer-term safety profile beyond the trial windows is not yet well characterized, and much of the human data comes from Chinese populations. The hedged reading is that the short-term profile looks similar in character to other incretin peptides, with the gastrointestinal effects concentrated around dose increases.

Reduced appetite is expected from the GLP-1 activity; the glucagon component is proposed to add energy-expenditure and liver-fat effects, but the human data cannot cleanly separate appetite-dependent from appetite-independent contributions.

Seek medical attention ifYou notice severe or persistent vomiting, signs of an allergic reaction, or severe abdominal pain.

Managing side effects

Many people find gastrointestinal effects ease as the body adjusts to a dose. Holding a dose steady before the next step-up and injecting after a lighter meal are commonly discussed ways to limit nausea.

FAQ

How common are side effects with mazdutide?In the trials gastrointestinal effects were the most frequent adverse events, mostly mild to moderate and dose-related. In the 9 mg arm, for example, vomiting, nausea, and diarrhea were each reported by a large share of participants. Rarer or long-term risks are not yet well characterized.
Do the side effects get better over time?Trial data suggests gastrointestinal effects were concentrated around dose increases and often settle as the body adjusts, though individual experience varies.
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This page is an independent educational reference and is not medical advice, and does not indicate any approval status for any use. Talk to a doctor before starting any compound.