Hidden sellers promote unlicensed weight-loss drugs through WhatsApp and Telegram competitions.
They offer injectable medicines as prizes to attract users.
The Guardian found groups advertising retatrutide, an experimental drug without approval.
Posts pressure users with 24-hour entry deadlines.
Experts warn these promotions create serious health risks.
They apply aggressive marketing tactics to unlicensed medicines.
One group offered retatrutide, Glow pens, and melanotan II as prizes.
None of these injectable products hold UK approval.
UK law bans the sale or promotion of unapproved weight-loss drugs.
Telegram and Meta say their rules prohibit such activity.
