Final answer:
Chemicals classified as Sensitizers can cause a severe allergic reaction. Allergens activate a primary IgE antibody response, resulting in a type I hypersensitivity reaction upon subsequent exposure. Anaphylaxis is the most severe allergic reaction.
Step-by-step explanation:
The chemicals that are classified as Sensitizers can cause a severe allergic reaction.
Type I hypersensitivities, also known as allergies, occur when a presensitized individual is exposed to an allergen. This exposure activates a primary IgE antibody response, sensitizing the individual to a type I hypersensitivity reaction upon subsequent exposure. The binding of the antigen to the IgE-primed mast cells causes the release of chemical mediators that elicit an allergic reaction.
Symptoms of allergies can range from mild to severe, and the most severe allergic reaction is called anaphylaxis, which requires emergency medical treatment. Antihistamines are commonly used to treat mild allergy symptoms.