Various reports suggest that people are experiencing unexpected allergic reactions to hair dye after contracting Covid-19, indicating that the virus may be permanently changing the immune system of a minority and making them vulnerable to new allergies, including to hair dye products which they may have used for many years without any ill effect.
One woman who had recently recovered from Covid-19 told the BBC she experienced an adverse reaction following a patch test for the same hair dye product she had used regularly for 10 years. Multiple anecdotal reports from within the industry also appear to confirm that clients are suffering allergic reactions to various hair dye products which they previously used safely.
There is currently no evidence of a direct link between coronavirus and allergic reactions, but the long-term effects of Covid-19 and its differing impact on certain individuals remains unclear. Researchers at Imperial College London are now investigating whether the virus does indeed have a permanent impact on some people’s immune systems in the same way that other illnesses do, making individuals more susceptible to allergic reactions to hair dye.
The National Hair and Beauty Federation (NHBF), the trade body that represents hairdressers and beauticians, is currently calling on all salons to carry out skin patch tests on existing as well as new customers to minimise the risk of allergic reactions among clients who may have only recently developed a sensitivity to hair dye ingredients like phenylenediamine (PPD). Many salons are now implementing compulsory patch testing for all clients, and this may be the only way forward in terms of minimising the risk of allergic reactions in the future.
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