Are hair dye reactions a thing of the past? A new product from Wella proves advances in technology could be the answer

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A trip to the hairdressers often fills me with dread - I can't bear having my hair washed and cut by a stranger, I'm weird like that - but that dread has turned to full-on fear on the few occasions when I've bravely opted for highlights.

We've all seen the photos and horror stories in the press where a girl has reacted to hair dye only to be left with hot, red, scaly patches and burns that could be with her for life; some women have even suffered an anaphylactic shock after a stint in the hairdressers' chair. These are of course the extreme end of the scale, but reactions happen in many ways and when you're stuck with sensitive skin, you're always looking out for the next potential risk.

Thankfully, despite not having the recommended (but rarely offered) patch test first, I've never reacted to hair colour myself but it remains a worry. I have memories of a friend at school coming back from an appointment at a nationwide hair salon chain with a scorched bald patch at her crown, where they'd tried to add some very cool purple streaks (it was the '90s) and instead burnt her scalp; that image comes back to me every time I consider going under the foils, and usually very quickly dissuades me.

As with all skin issues, there are two possible kinds of reactions; that of an allergic reaction, or simply an irritation (contact irritant dermatitis). These vary from mild redness and discomfort to the extreme examples above; if you have sensitive skin, there's a good chance you'll fall into one of the categories as the dyes are pumped full of chemicals.

"Permanent hair dyes or ‘para dyes’ contain a number of chemical ingredients and each one carries a degree of risk," explains Glenn Lyons , Clinical Director at The Philip Kingsley Trichological Clinic.

"Some of the ingredients in tints can also irritate the scalp , causing itching and burning. If the mixture is too strong, left on too long or repeated too often, damage can occur to the hair resulting in breakage, and to the scalp which can become quite sore."

Cosmetic Dermatologist Dr Sam Bunting  agrees: "PPD dyes usually come packaged in two bottles – the oxidation of PPD leads to an intermediate, partially oxidised form that can cause allergy in sensitive individuals. This reaction varies – it can be mild, causing red, dry scaling (dermatitis) on the tops of ears and eyelids; however in more severe cases it will cause fierce inflammation and swelling on the scalp and face. Eyelids may swell and close, and the reaction may spread to other sites on the skin. I’ve seen a few rare cases so severe they’ve required hospitalisation."

While the less severe damage to the hair and scalp can usually be solved, strong reactions could lead to dire consequences. "Permanent damage only occurs as a result of damage to the scalp that leaves a scarred area – incorrect application of bleach, for example in highlights, can result in a chemical burn. This is very rare, but can have disastrous results," reasons Glenn.

"In rare cases, an allergic reaction to the dye can occur – usually to the paraphenylene diamine which is in the darker shades – and this can be quite severe causing a rash which may weep, and swelling of the face and neck. In extremely rare cases the allergic reaction can be fatal."

MORE GLOSS: Makeup and skincare ingredients to avoid if you have sensitive skin

See? FEAR. So it is good news, then, that a new dye has launched that actually reduces the risk of developing allergy. Created by king of all things colour Wella Professionals, Koleston Perfect Innosense is a new professional hair colour brand which is formulated with ME+, a brand new dye molecule which offers the same high standard of colour while reducing the potential for allergic reactions thanks to something as simple as its shape.

How does it work? PPD (para-phenyleneadiamine) and PTD (para-toluenediamine) are the ingredients that are usually to blame for hair dye reactions, and are used in the patch test that's recommended before treatment. It's these two ingredients which have been replaced with the new, innovative ME+.

"ME+ (chemical name 2-Methoxymethyl-p-Phenylenediamine) was developed over a period of 20 years," explains Kathy Rogerson, P&G Sci-comms UK and Ireland. "Allergic reactions occur when a substance is considered harmful by the body’s immune system. This process is triggered when a molecule fits with a receptor on the surface of a T-Cell (one of the body’s immune system ‘gatekeepers’) and is identified as potentially harmful.

"Using the latest techniques in colour technology, scientists at P&G have altered the molecular structure of pPD to reduce the allergenicity of this molecule. By modifying pPD into a molecule that does not easily fit with the T-cell receptors and is therefore less likely to be considered as harmful, the risk of developing allergy is reduced with ME+ (vs pPD/pTD)."

Of course, the new technology isn't foolproof and the clue is very much in the wording. 'Reduces' the risk means there is still a chance you'll leave the salon red-faced as well as red-headed but this is a great step in the right direction. It's also only available as a permanent hair colour - it's how ME+ is formulated and it wouldn't work for semi-permanent dyes. Colour chameleons will be glad to know, however, that the new molecule doesn't compromise on quality. "ME+ is the first hair dye advancement in 100 years to deliver full permanent colour performance and full colour spectrum, while allowing for hair colour formulations with reduced risk of developing allergy compared to pPD or pTD based formulas," Kathy assures me.

As a precaution, an allergy test should always be taken 48 hours before each colour session to ensure you're safe, just as you would with any other dye, but it's encouraging to see that brands are taking allergies and reactions seriously. Wella Professionals Global Creative Director, Colour, Josh Wood  says of the launch: "People who colour their hair are increasingly aware of product ingredients and are conscious of the choices they make. Koleston Perfect Innosense offers them the same perfect results they would expect from the brand but with a reduced risk of developing allergy."

This way, you can worry more about what your hairdresser is planning to do with those scissors rather than dreading your highlights...

Wella Koleston Perfect Innosense is available in all Wella salons