What Causes Allergies?

Hundreds or possibly even thousands of ordinary substances (allergens) may trigger an allergic reaction.

Common allergens include:

• Animal dander
• Drugs/medications such as penicillin
• Household dust or dust mites
• Insect stings such as bee stings or fire ant stings
• Molds
• Plant pollens such as poison ivy
• Latex
• Industrial chemicals
• Cockroach droppings
• Fragrances
• Jewelry
• Cosmetics
• Other substances