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. Systemic antihistamines (antipruritics) such as hydroxyzine or cetirizine against prescription may be helpful. Even addition of corticosteroids has possible benefits.
Some products are used to mask the unwanted hair. It mainly contains hydrogen peroxide and sulfates.