Detailed answer

Blackheads, also known as open comedones, occur when hair follicles become plugged with excess oil and dead skin cells. They are not typically caused by an allergic reaction to skincare ingredients. Allergic reactions to skincare products commonly manifest as redness, itching, rashes, or hives. Blackheads are primarily caused by factors such as excess oil production, hormonal changes, or the buildup of bacteria on the skin. However, certain skincare products or cosmetics that are comedogenic or pore-clogging can exacerbate the formation of blackheads. It's essential to choose non-comedogenic or non-pore clogging products to minimize the occurrence of blackheads. If you suspect an allergic reaction to a skincare product, discontinue its use and consult a dermatologist for further evaluation and advice.