Like many women her age, Charlotte* has dabbled with tweakments – trying out Botox in her forehead and filler in her cheeks. But the effect was not as she’d hoped and last year, she decided to have the filler removed.

The filler didn’t sit on her face as she’d hoped – it was “mushing around and migrating,” says Charlotte, who is 38 and lives in Stoke-on-Trent. In January this year, she went back to the clinic that had put in the filler. As she was a regular client, they offered to dissolve it for free. She had injections of hyaluronidase, a commonly used enzyme that breaks down the filler.

This was when the problems started. Instead of improving her appearance, she says the dissolving of the filler caused her skin to become stretchy and loose. “I felt fine for three to four weeks, but then the systemic issues began,” she says. She also describes constant pain, shakes, internal tremors “like ants under the skin”, insomnia, and muscle weakness.

This year, in a bid to make sense of her health problems, Charlotte has spent around £5,000 on MRI scans, private blood tests and consultant fees. No answers have come through these investigations.

“My life just went downhill,” says Charlotte. Prior to this, she was a “youthful 35-year-old”, she says, working out every day, with an athletic figure and six-pack. “Now you can just pull skin off my face and body – on my arms, normally I’d see a tricep. It hangs off like I’ve been 30 stone and lost loads of weight. I don’t know how I’m ever going to get over the fact that this is my body now,” she says.

Her concerns go beyond looks. She has two young daughters and runs a finance firm with her husband, but was barely able to work for the first half of this year. “I was disabled, bedridden. I thought I had MS because I’ve got such bad nerve issues,” she says.

Charlotte is one of many people who’ve chosen to have facial fillers removed amid a growing trend towards more natural aesthetics.

Recent years have seen a marked shift away from the plump, generously-syringed look that once filled our Instagram feeds. Celebrities including Kylie Jenner popularised inflated lips and lifted cheekbones, but the beauty tides have since turned somewhat. Reality TV stars like Molly-Mae Hague and Chloe Sims have spoken about dissolving their filler in pursuit of more “natural” beauty.

But while many who dissolve do so without issues, some experience serious complications. Rather than snapping back to their previous faces, these tweaks can in extreme cases be disfiguring and life-changing. Charlotte and others like her are sharing stories in WhatsApp groups, subreddits, and Facebook communities with tens of thousands of members. Like Charlotte, commonly-shared worries are stretchy, loose skin, facial hollowness and searing pain.

A study from April this year coined the term “post-hyaluronidase syndrome.” It found that 17 to 18 per cent of cases they studied complained of “facial changes such as hollowing.” The study found that the risk of getting adverse effects had “nothing to do with the actual dose of hyaluronidase”, explains Daniel Ezra, founder of the cosmetic Ezra Clinic and oculoplastic surgeon, who worked on the paper. “[It’s] more about the filler, how long it was there for, and how much was put in. So the more you put in and the longer it’s there for, the riskier it is.”

Julianna*, who is 36 and lives in London, is one of these people. “I’m not a person who does a lot of fillers,” she says. “I had one little drop done a year ago, where I had unevenness of skin, to plump it up.” It was advertised to her as something that would dissolve by itself within six to nine months. She waited for that to happen, but after a year there was still a bump where she smiled. “Now I think, gosh I should have left it,” she says.

Julianna had read up about hyaluronidase and knew that complications could occur, but felt like the chances were slim. She asked if she could have “the tiniest possible injection”. She says only a very small amount was put into her skin: 20 units. An allergy test was done prior to her procedure, with no reaction.

When Julianna came home, she noticed an area on her face where she’d had no filler – her under-eye tear trough – was “disappearing, it was melting.” One side of her face looked totally different to the other. “It was spreading like crazy. It was burning, like itchy sunburn from inside.” There’s now a laxity to her skin. “When you touch your skin, you usually feel some resistance. With this, it’s almost like it’s not connected to anything – it just moves left and right, no attachment.” A four-centimetre dent remains under her eye. With her wedding planned for 2025, she wants answers.

Both Julianna and Charlotte raise concerns about the lack of regulation of beauticians. “The beauty industry is like the wild west,” says Julianna. In Lilly and Julianna’s cases, their injectors were sympathetic and concerned, but ultimately dismissive that hyaluronidase could have caused their issues. Charlotte describes feeling “gaslit by doctors – we’re just on our own”.

When Lilly*, 28, from Glasgow, approached her injector after her negative experience with hyaluronidase, she was told to get her hormones checked.

In July, Lilly felt unhappy with the look of her lip filler and went to get it dissolved. Afterwards, she experienced swelling across her face and pain in her leg. “Volume all over my face was lost. My eyes had become sunken and dark, and my skin just looked grey.” Lilly’s eyebrows and hair also began falling out, and the skin under her chin started to sag.

For Lilly now, even leaving the house is difficult. She believes she’s developed an inflammatory response triggered by the dissolver. “I can’t drink alcohol, go to the gym, go out to dinner, drinks with friends. I used to travel a lot, but I can’t do that either now. I don’t do much, to be honest.”

Daniel Ezra says patients should be informed about the risks of the filler, and that having it dissolved is “a very, very difficult set of decisions to make. Of course, it’s coupled by the fact that the filler doesn’t really go away in the way we thought, and it can persist for many, many, many years – decades, even.”

For the rarer complications – the systemic issues as reported by Charlotte and Lilly – the study did not have enough data to draw any conclusions. Ezra does mention that hyaluronidase has been used for decades for cataract surgery, and no issues like these have been reported, but they will “keep an open mind, and try to understand”.

Dr Leah Totton of Dr Leah Cosmetic Skin Clinics says that hyaluronidase should only be used in emergency and extreme circumstances, and “should not be used to tweak minor results.” She says this should be to “treat avascular necrosis (a disease that results from the temporary or permanent loss of blood supply to the bone) or impending avascular necrosis, or where there is a clear cosmetic defect where the use of hyaluronidase can be justified.”

She adds that the hyaluronidase “is something that needs to be prescribed by a doctor in a medical clinic that has the facilities, training and staff to manage emergency situations if a patient were to have a severe allergic reaction”.

While much of the cosmetic injectable industry is unregulated, Save Face offers a government-approved register of practitioners that are inspected for safer tweakments.

But for people like Charlotte, these dangers weren’t apparent when receiving the injections. “You go into these things thinking everything’s safe, you dissolve it, then you find out it’s not just me having a reaction,” she says. “It’s ruined my life.”

*names have been changed