When Was Mounjaro Invented, and When Was It Approved?

Tirzepatide is a synthetic peptide developed by Eli Lilly and Company. Research into dual incretin receptor agonism — targeting both the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor simultaneously — was an active scientific pursuit through the 2010s, and tirzepatide emerged as a clinical candidate from that work.

Key milestones in tirzepatide's history

• Clinical trials (2018–2022): Tirzepatide was evaluated in a series of large clinical trials examining its effects in adults with type 2 diabetes and, separately, in weight management. These trials generated the evidence base that regulators reviewed.
• Initial regulatory approval: The medicine was first approved in the United States in 2022 for type 2 diabetes under a different brand name. Its development for weight management followed closely, building on the same active substance.
• UK approval for weight management: Mounjaro (tirzepatide) received regulatory approval in the UK for chronic weight management in adults in 2023, following review by the relevant UK authorities. It became available through prescription in the UK from late 2023.
• Ongoing monitoring: As a relatively recently approved medicine, Mounjaro carries a black triangle (▼) designation in the UK, meaning it is subject to additional monitoring. If you experience side effects, you can report them to your national reporting scheme (such as the UK's Yellow Card scheme) and discuss them with your healthcare professional.

For a broader overview of what Mounjaro is and how it works, see our Mounjaro information hub. It is also worth knowing that Mounjaro is currently available only as an injectable pen — if you have come across questions about Mounjaro in tablet form, that page explains what is currently known.

Knowing when Mounjaro was developed is one piece of context; staying consistent with your own prescribed treatment is where a tracking app can genuinely help. GLP Trackr is built specifically for people already on Mounjaro or Wegovy, and the dose-logging feature is a natural starting point — every injection can be recorded with its date, time, and strength, so you always have a clear history of where you are in your treatment.

Alongside dose logging, the injection site tracking feature lets you record each site (abdomen, thigh, or upper arm) and get a suggestion for your next rotation, taking one more thing off your mental checklist. If you want to capture how you feel week to week — energy, mood, any side effects — the daily check-in builds a picture you can bring to your prescriber appointments.

GLP Trackr does not provide medical or dosing advice, and nothing in the app replaces the guidance of your prescriber or doctor. If you have any concerns about your treatment, your healthcare professional is always the right first contact.

Ready to bring your Mounjaro journey into one place? Download GLP Trackr on the App Store or Google Play — there is a free 7-day trial waiting for you.