Weight-loss wonder drugs go rogue online: What’s inside the vial?

Vials are advertised alongside prices, dosage calculators and instructions for mixing and injecting them. (AI Generated Image)

11 min readOct 19, 2026 07:15 AM IST First published on: Oct 19, 2026 at 07:11 AM IST

For people who have battled obesity for years, the promise of losing a quarter of their body weight is hard to ignore. The success of weight-loss drugs such as semaglutide and tirzepatide has fuelled a global appetite for more powerful treatments. Now, experimental drugs retatrutide and zenagamtide are generating a fresh wave of excitement with striking clinical trial results but there’s a downside — they are finding their way into the online marketplace before they have even been approved for routine use.

Retatrutide and zenagamtide are attracting attention for their potential to transform obesity treatment. Neither has been approved for routine weight-loss treatment, yet online sellers are offering products under their names, while social media influencers discuss their effects and share links to suppliers. Some videos even demonstrate how to reconstitute powdered compounds and self-inject them. A report in JAMA has highlighted how readily these experimental compounds can be found online, raising concerns that people may be using them outside clinical trials and without medical supervision.