In phase 2 clinical trials, retatrutide was given in the following doses:

• 1mg, 2mg or 4mg (starting dose)
• 1mg, 4mg, 8mg or 12mg per week (maintenance dose)
• 12mg per week (maximum dose)

The dose escalation was similar to other weight loss medications, with the retatrutide dose increasing every 4 weeks.

However, there is no ‘official’ retatrutide dosage schedule yet because it’s still being researched for its effects on weight loss. Like other weight loss injections, retatrutide was started at a low dose and gradually increased over several weeks, to allow the body to get used to the medication and minimise the chance of side effects.

If retatrutide is approved for weight loss, the dosage schedule will be confirmed, and it will only be available with a prescription. You will also need to meet specific criteria before a doctor will approve it for you.

Is retatrutide an injection?

Yes, retatrutide will be available as a once-weekly self-injectable medication, similar to other weight loss injections. Although the official dosage schedule is not yet known, it will likely start at a low dose and increase gradually until you reach the maximum maintenance dose. This will help the body get used to the active ingredient and lower the chance of side effects.