Doctors have issued an urgent warning over a growing trend – driven by social media – for self-injecting the anti-wrinkle treatment Botox.

Sounding the alarm, experts say that the practice risks serious allergic reactions, paralysis, long-lasting swelling and could even prove fatal.

Thousands of videos have been posted on TikTok in recent months, with women sharing tips on how to perform so-called ‘backyard Botox’. In one, a British woman gives a tutorial to her 15,000 followers explaining how she self injects – as well as where she purchases the prescription-only drug.

She said: ‘I have hooded eyes and I hate them, this lifts them, and that’s what I love about Botox.’

The video then goes on to show her injecting multiple times around her face, as she explains she used to get it done by a professional but now does it herself.

Botox is the most recognised brand of the botulinum toxin, used to paralyse facial muscles with the aim of reducing wrinkles. But it is derived from one of the most poisonous biological substances on Earth – a toxin produced by the Clostridium botulinum bacterium, which also causes the deadly botulism food poisoning.

DIY kits to self-inject Botox can cost as little as £50 online compared to about £400 for treatment with a specialist.

However, Dr Nikita Desai, a cosmetic specialist at the Harley Street Skin Clinic, says: ‘People are taking ridiculous risks when they self-inject.

Thousands of videos have been posted on TikTok in recent months, with women sharing tips on how to perform so-called ‘backyard Botox’

DIY kits to self-inject Botox can cost as little as £50 online compared to about £400 for treatment with a specialist

‘There are multiple ways this can go wrong. Firstly, if you purchase these products online, you do not know what you are injecting – and this is a potentially deadly toxin.

‘The margin of error when you are injecting is millimetres, and there can be serious problems if you place it in the wrong place.’

She says side effects include nausea, vomiting, loss of vision and life-threatening reactions.

Mr Mo Akhavani, co-founder of The Plastic Surgery Group, says: ‘There is a serious risk of an allergic reaction, which would cause an anaphylactic shock, and when this happens at home you will not have the response kit needed which means it could be deadly.

‘You also risk causing yourself permanent nerve damage and constant pain if you inject into the wrong place. Then there are the cosmetic risks – overdoing it can cause a puffy appearance that can take months to resolve itself, or it can lead the face to look droopy, as if you have had a stroke.’

Botox was originally developed as a chemical weapon – exposure to even tiny amounts can cause paralysis and death within minutes. Its use was explored by both sides during the Second World War, though it was never deployed.

In the 1960s, an eye surgeon began experimenting with it as a non-surgical treatment for strabismus, a muscle disorder that causes crossed eyes.

Injected in minuscule doses, the toxin paralysed the targeted muscles, correcting the eye problem, without affecting the rest of the body – but patients also noticed that their wrinkles faded.

Decades later it was reborn as a cosmetic treatment: Botox.

Experts say that the practice risks serious allergic reactions, paralysis, long-lasting swelling and could even prove fatal

Mr Akhavani says: ‘The key thing to remember is that this is a prescription drug.

‘These are medicines that should be administered by a professional in a safe clinical setting, not your living room.’

It is estimated that more than 900,000 Botox injections are carried out by professionals in the UK every year.

But analysis of side effect reports recorded by the UK medicines regulator, the MHRA, has revealed the number of complications using these injections is now four times higher than it was before the pandemic.

The most common side effects recorded include loss of vision, allergic reactions and paralysis.

‘We have seen a massive rise in “do it yourself cosmetics” since the pandemic,’ says Dr Desai. ‘And it is putting people in harm’s way.’

One of those who is buying Botox online and documenting her journey on TikTok, contributing to the trend, is Zoe Shilton. The 48-year-old says that she became ‘addicted’ after she started injecting herself with Botox two years ago.

Now she injects herself twice a year – under her eyes, on her forehead and the sides of her mouth.

‘I am obsessed with the results and how it has made me feel,’ says Zoe from Kent. ‘I know there are risks but it is like anything risky, such as going down a water-slide – you just do it and there is a thrill.’

Nearly a decade ago Zoe did go on a course to learn how to administer the injections, but experts still warn that this is not safe.

She adds: ‘I may have had training but I know loads of women doing this, and without training you would have to be crazy.’