A new beauty trend that involves getting salmon sperm injected into your face can leave your skin bruised and covered in specs of blood.
That's according to advocates of the wrinkle-defying tweakment.
As well as Botox-like effects, polynucleotides – which can cost in the region of £400 – are said togive customers a 'baby face' and rejuvenated skin.
But TikTok videos posted by women who have had the injections show them left with lumpy skin that looks like 'bee stings'.
Others have showed pictures of them being left with bruises and dried blood, saying the old adage of 'beauty is pain' really is true.
Aesthetic nurses who offer the treatment insist the bruising is only temporary.
Sharing her experience on TikTok @donatsuyang, who has more than 9,900 followers, said she 'looked like an absolute lunatic at dinner' because she had 'dried blood and bruises' on her face
One TikTok user with nearly 10,000 followers said that she 'looked like an absolute lunatic at dinner'.
She showed her post-injected face, which was covered in small lumps, specs of dried blood and small bruises.
'Basically salmon sperm equals baby face and this is what I have to go through for now,' she said.
'I have got little bumps and bruises on my face. But beauty is pain, am I right?'
An aesthetic nurse based in Surrey with just over 1,000 followers also posted her face just after getting the treatment under her eyes.
Although the video showed her eyes were visibly swollen, she said the treatment caused 'minimal' pain and she 'could hardly feel it'.
She added that she had a 'little swelling' that subsided that evening and completely disappeared by day three.
Another TikTok video posted by someone with more than 4,800 followers showed her getting the injections at a clinic.
Afterwards, her face was lumpy and covered in blood.However, at the end of the video she shared her blemish-free skin completely healed.
Advocates say polynucleotides offer a 'natural' alternative to other traditional 'tweakments' such asBotoxand filler.
Some doctors claim it is safer than other cosmetic injectables, which have been linked to a catalogue of complications including blocked blood vessels, lumpy skin and infections.
It typically uses purified and sterilised DNA molecules extracted from salmon or trout sperm, known aspolynucleotides which have anti-inflammatory effects.
South Korea's aesthetics sector has been using the treatment for over a decade but it's now gaining popularity among Western celebrities, includingJennifer Aniston, who told The Wall Street Journalshe is reaping its skin rejuvenating qualities.
When polynucleotides, DNA molecules extracted from fish sperm, are injected into humanskin, fibroblasts are activated.
Fibroblasts are stretchy molecules found in skin that help to maintain the structural framework of the tissue. As we age these fibroblasts decrease.
So, when thepolynucleotides are injected under the eyes, in the cheekbones or in the neck, it theoretically 'rejuvenates' the skin.
An aesthetic nurse @the_art_of_beauty based in Surrey who has just over 1,000 followers, also posted a video of her face just after getting the treatment under her eyes.She said that she had a 'little swelling that subsided that evening and had completely gone by day three'
Another TikTok video posted by @hi.vega who has more than 4,800 followers, shows her getting the injections at a clinic. Post treatment her face is lumpy and covered in blood
Although they are 'safer' than getting filler or Botox, they are still painful and will cause bruising, experts warn.
Emma Wedgwood, an aesthetic nurse who works in a Harley Street clinic and offers the treatment, compares the initial side effect of bumpy skin to 'bee stings'.
But she told MailOnline this bumpy swelling goes down within a day or two.
'Sometimes you get bruising depending on where you're injecting,' she said.
'It's usually the more delicate areas such as the eye which are more susceptible.
'But not it's not in the same way as filler where you would pretty much expect bruising from filler and it is a bonus if you don't, with polynucleotides it's the other way around.'
Once the swelling has reduced and the skin starts to heal, it can still take months to see the full wrinkle busting effects.
Ms Wedgwood said: 'It can be frustrating for the patient because they have to wait.
'You are looking at about three to six months to see the full effects. So, it's not an overnight job.'
The popular fishy injectable has been a staple skincare treatment in South Korea for more than a decade and now celebrities including Jennifer Aniston (pictured) are reaping its skin rejuvenating qualities
The beauty treatmentuses purified and sterilised DNA molecules extracted from salmon or trout (pictured) sperm, known as polynucleotides, and some doctors claim it is safer than other cosmetic injectables
Aesthetic nurse Amanda Azzopardi also offers polynucleotides (pictured a patient) and explains because a very fine needle is used and the product isn't thick, the bruising 'shouldn't be extensive'
Aesthetic nurse Amanda Azzopardi also offers polynucleotides in her clinicsin London, Liverpool and North Wales. She explains the injections will bruise the skin, just like any other injectable.
Because a very fine needle is used and the product isn't thick, the bruising 'shouldn't be extensive', she says.
But patients should be warned that the area will sting for about a minute and it may take a week for bruising to heal.
'It's still aninjectable treatment,' she told MailOnline.
'So, you're going to have minor side effects such as redness, bruising, inflammation, which will last about a week. There is no risk of vascular occlusion.'
However, there is always a risk of allergic reaction. MsAzzopardi said you should ask about allergies in your medical consultation and raise if you have a fish allergy.
