Is Retatrutide legal in United Kingdom?

The MHRA states that retatrutide is a medicine still in clinical development that has not been authorised for use in the UK; outside authorised clinical trials, products sold as retatrutide are likely to be illegal. It says anyone selling it is doing so illegally and that such products are untested for safety, quality or effectiveness. The MHRA's Criminal Enforcement Unit seized more than 2,000 unlicensed retatrutide and tirzepatide pens in Northampton in October 2025, raided two premises in February 2026 believed to have been used to make retatrutide, tirzepatide and peptide products, and arrested two people in a raid near Northampton in May 2026 that recovered around 12,000 doses of unlicensed weight loss products.