Hi, welcome to the forum, your
symptoms are suggestive of Atopic dermatitis or Contact dermatitis. Usually allergens are small molecules which can penetrate the layers of the skin and sweating is known to enhance this action. Stinging insects, Aeroallergens (uncommon), Foods and additives like Milk, egg, peanuts, nuts, soy, and wheat are the most common agents to cause such reactions.
Topical lotions such as calamine decreases pain and pruritus.