Black market weight-loss drugs left a woman thinking she was going to die after do-it-yourself injections put her in hospital.
Paige Roberts, 24, looked for anti-obesity medication on social media after her GP advised her to lose weight.
After the first self-administered injection of what she was told was semaglutide – diabetes medication which is illegal to sell without a prescription – she started vomiting and feeling dizzy and sick.
The Royal College of GPs (RCGP Cymru) said buying weight-loss drugs without prescription was highly dangerous.
Ms Roberts, a healthcare assistant from Llandudno, Conwy county, does not qualify for weight-loss medication on the NHS as she weighs 13st (82kg) and has a body mass index of 28.5, so she is not classed as obese.
She said she was told weight loss could help her start having periods again after they stopped due to bloating caused by polycystic ovary syndrome.
She spent £80 on four pre-filled syringes with instructions to use one a week for four weeks.
She was not initially worried as nausea was a known side effect, but went to A&E at Ysbyty Glan Clwyd when she was still vomiting after 48 hours.
Staff told her lots of people had been admitted to hospital after taking weight-loss drugs and Ms Roberts said she was informed many on the black market were amphetamine-based.
“I was worried I was going to die of dehydration because I couldn’t keep anything in my stomach,” she said.
After liver and kidney function tests and time on a drip, Ms Roberts was allowed to go home, but she said she wanted others to be aware of the dangers.
She added: “Influencers on social media platforms like TikTok and Instagram only show the good things that happen and say ‘look how good we look’, which makes you think you can get that as well.”
Ms Roberts also believes the injections were “too easy” to get hold of without professionals to prescribe or advise.
RCGP Cymru said prevention and good nutrition were better solutions than weight-loss medication.
“Acquiring weight-loss drugs online without prescription is highly dangerous,” it added.
The Medicines and Healthcare products Regulatory Agency previously warned people not to buy pre-filled pens claiming to contain weight-loss drugs, but to consult a healthcare professional qualified to prescribe medicines.
UK government health secretary Wes Streeting said weight-loss drugs could be “game changers” when taken alongside a healthy diet and exercise, but warned against taking the drugs without medical supervision.