Retatrutide vs Tirzepatide
Side by side: what studies show, whether it is legal, doping and risks. No winner is shown on purpose.
| Retatrutide | Tirzepatide | |
|---|---|---|
| Type | A substance under study that mimics three hormones linked to appetite and blood sugar. Not approved in the EU or US. | A medicine that mimics two gut hormones, GIP and GLP-1, which affect appetite and blood sugar. Approved in the EU and US for type 2 diabetes and obesity. Approval covers only these medicines. |
| Stage | Still being studied | Approved medicine |
| Is it legal (PL) | No approval. The European medicines database (EMA) lists no such medicine in Poland (9 October 2026). The Polish register was down, so we could not check it directly. | Prescription only. The EU-wide approval of Mounjaro covers Poland. The European medicines database (EMA) shows no separate Polish product (9 October 2026). |
| Is it legal (EU) | No approval. The European medicines database (EMA), which covers EU and national approvals, lists no such medicine (9 October 2026). | Prescription only. Approved across the EU as Mounjaro. This covers that medicine only, not products sold outside pharmacies. |
| Is it legal (US) | No approval. The FDA drug register has no such medicine. | Prescription only. Prescription medicine (Mounjaro). |
| Doping | May be banned, WADA 2026 | Allowed, being watched, WADA 2026 |
| Safety | Little data | Well known |
| Risk of fakes | High | Medium |
| Fat loss | A Effect in studies. Early and large studies show big weight loss: 18.8% at the highest dose and 5.1% on placebo, in adults with diabetes. No medicine is approved yet, and this grade says nothing about products sold online. | A Effect in studies. Weight fell by 20.9% on average at the highest dose studied, and by 3.1% on placebo, after 72 weeks. In people with diabetes it fell 12.8% to 14.7%, and 3.2% on placebo. Weight came back after stopping. The maker paid for the studies, which tested the pharmacy medicine. |