A teenager claims a counterfeit "Kylie Jenner lip kit" caused her top lip to blister and balloon up "like a slug", leaving her needing urgent medical treatment.
Larissa Reynolds bought a fake version of the cult product for AUD$8.50 in April where it languished in her make-up drawer until last week.
With the real product retailing for AUD$37, the fake seemed like quite the bargain.
The 19-year-old carer for the elderly wore her copy of the matte liquid lipstick in shade Love Bite with no apparent problems when she went out with friends for the night.
But by the following morning, Larissa's lip started to tingle and swell to the size of a 10-cent piece, prompting the teen to rush to emergency doctors for fear her "lip was going to drop off'.
"At the end of the night there was a tingling sensation on my lip but I didn't think anything of it," Larissa, from Warwickshire in the UK, said.
"When I woke up it was a small lump which was pretty sore. As the day went on I could feel it getting bigger and bigger – it felt like my lip was going to drop off.
"At its biggest size it was yellow, it looked like I had a slug on my lip, and it was hanging over my bottom lip, it was horrible."
Larissa put ice on her lip in a desperate bid to reduce the swelling and rang a friend who urged her to go to hospital.
"I felt quite ill and was a bit run down," Larissa explained.
"I tried ice but it just took the swelling down a tiny bit – as it got bigger it went yellow, too.
"I couldn't get to A&E so rang my doctors and got an emergency appointment where my GP confirmed it was definitely an allergic reaction and I was told to throw the lip kit away.
"I was advised to take allergy relief medication which I bought over the counter and was told if it got worse and started to affect my breathing to call 999.
"It's quite frightening to think fake make-up can cause a reaction like that."
Larissa bought the fake make-up over Facebook, from a young woman who also sells the products at outdoor markets. The teen is is now speaking out to urge young women not to risk their health by buying counterfeit cosmetics.
"I want to show people what could happen if you buy fake make-up," Larissa said.
"It's tempting because the real thing is a lot more expensive and I got mine for just $8.50.
"The swelling has gone down but it still feels cracked underneath.
"I don't want anyone else to have the same reaction as me. I want everyone to know it's just not worth it – I've learned the lesson the hard way."
Antonia Mariconda, the founder of awareness campaign Safety In Beauty, said counterfeit make-up is a key concern for the organisation.
"Fake cosmetics continue to remain a top five priority of concern at Safety in Beauty," Antonia said.
"With social media increasingly adding pressure certain brands have become status symbols and high prices are driving younger customers to seek out cut-price bargains.
"Fake cosmetics contain potentially dangerous sub-standard ingredients that can lead to serious skin reactions and have long term implications – we urge all people looking for cut-price brand cosmetics to not buy online unless from reputable sources and online retailers.
"If unsure please check with customer services of the brand and they'll be able to quickly tell you if the product or brand is genuine."
A Facebook spokesperson said fraudulent items were prohibited from being sold on the site.
"Items, products or services sold on Facebook must comply with our Community Standards, as well as the Commerce Policies," the spokesperson said.
Additional reporting by Caters