How do I explain becoming allergic to my client who “knows better”?

Pergunta:

I have a nail client who is a doctor. She has stated that becoming allergic to something usually happens after 2-3 exposures. In her understanding of immunology, as she has been exposed to a specific nail brand for 4+ years, she is unlikely to become allergic to it.
To put this in context, I have suspended the use of the nail brand I was using because of all the problems that appear to be linked to it. I haven’t experienced any issues, and neither has she, but I still felt the need to do so.
Você pode me dar algum conselho ou resposta? Quero explicar a ela como ela e meus clientes ainda podem desenvolver um problema.
I feel she doesn’t trust my judgment and I can’t give her enough scientific answers other than showing her images.

Resposta:

Allergy is a very diverse chronic system disease. According to various immune responses, there are 4 types of allergic reactions. Each of these types involves different immune cells and proteins (Immunoglobulins). Among the 4 types of hypersensitivity types, I (immediate reactions) and IV(delayed reactions) are of interest to nail techs and their clients because of the presence of potential allergens in professional nail products.

The particular ingredient inherently is not an allergen, but it can become an allergen when it comes into contact with proteins in our body. This type of allergen has its own name – hapten. For instance, the immune system won’t react to HEMA. However, it can respond to the hapten complex of HEMA and our own proteins. It is practically impossible to predict whether the reaction develops because all immune reactions involve multiple factors, including individual reactivity of the immune system, the presence of other conditions, infectious diseases, etc.

There are many people who never develop any allergy. However, the risks of an allergic reaction increase when the wrong salon practice takes place. For instance, when an uncured product comes into contact with skin or when a nail pro uses invasive methods like ‘Russian manicure’. I am happy that your client doesn’t develop the allergy and I hope the safer practice you use will prevent the issue in the future. 

Você também pode recomendar ao seu cliente a leitura deste artigo, especialmente se ele for médico.
Type IV Hypersensitivity Reaction – StatPearls – NCBI Bookshelf (nih.gov)

E, é claro, há também o nosso Alergias e como elas ocorrem curso.