An allergy is a immune malfunction whereby a person's body is hypersensitised to react immunologically to typically nonimmunogenic substances. When a person is hypersensitised these substances are known as allergens. The word allergy derives from the Greek words allos meaning "other" and ergon meaning "reaction" or "reactivity". Reactions can vary from the benign runny nose, to life-threatening anaphylactic shock and death.

Acne is the term for plugged pores (blackheads and whiteheads), pimples, and even deeper lumps (cysts or nodules) that occur on the face, neck, chest, back, shoulders and even the upper arms. Acne affects most teenagers to some extent. However, the disease is not restricted to any age group; adults in their 20s - even into their 40s - can get acne. While not a life threatening condition, acne can be upsetting and disfiguring. When severe, acne can lead to serious and permanent scarring. Eve...