When people with obesity take retatrutide, the most common side effects are stomach problems like nausea or diarrhea. These tend to happen more and get worse when the dose is higher, but starting with a lower dose (2 mg) might help reduce these issues.

People with obesity or type 2 diabetes who take a drug called retatrutide are more likely to get stomach issues like nausea, throwing up, or constipation—especially if they take higher doses (8 or 12 mg per week). But most people don’t have to stop taking it because of serious side effects.

Taking a weekly shot of retatrutide might make you feel more nauseous, throw up, get constipated, or have allergic reactions than if you took a fake shot — but these side effects aren’t life-threatening and are kind of expected.

A shot called retatrutide, given once a week, helped people with obesity lose nearly a quarter of their body weight over a year—some losing around 57 pounds—much more than those on a dummy shot.

People with obesity who took a shot called retatrutide once a week for a year lost nearly a quarter of their body weight—way more than those who got a dummy shot. This makes it one of the strongest weight-loss medicines we’ve seen so far.

Taking a drug called retatrutide can shrink your waist by nearly 8 inches over a year if you're an adult with obesity, which means you're losing dangerous belly fat that's linked to heart and metabolic problems.