What is a key sign of an allergic reaction to nail products?

Redness and swelling around the nail are key signs of an allergic reaction to nail products because these symptoms indicate an inflammatory response to allergens found in the products. Allergic responses often manifest as localized inflammation, which can include swelling and erythema (redness) in the affected area, such as around the nails.

This reaction occurs as the body's immune system identifies certain substances in the nail products—like certain chemicals used in polishes, glues, or even artificial nails—as threats, leading to a response that causes blood vessels to expand and fluid to accumulate, resulting in redness and swelling.

While itching and dryness, heat with discoloration, and thinning or peeling of the nail may be associated with other conditions or irritations, these do not specifically represent the typical signs of an allergic reaction. Itching and dryness, for instance, can be symptoms of irritation rather than a true allergic response. Heat and discoloration could align with infection or other issues, and thinning or peeling of the nail might suggest a different kind of nail pathology rather than an allergy to products. Thus, redness and swelling stand out as the hallmark indicators of an allergic reaction.