Online sellers promote unlicensed weight-loss drugs through WhatsApp and Telegram giveaways.
They offer injectable medicines as competition prizes.
The Guardian found groups advertising retatrutide, an unapproved experimental drug.
Posts pressure users with 24-hour deadlines.
Experts warn these promotions pose serious health risks.
They apply aggressive marketing to unlicensed medicines.
UK law bans advertising or selling unapproved drugs.
Platforms say they prohibit illegal drug sales.
