Publications
Partners
An allergy is caused by an abnormal reaction to a harmless substance.
The human immune system is geared toward protecting the body against invaders like bacteria, viruses and certain harmful chemicals. For some people, though, the immune system reacts abnormally to an ordinarily harmless substance.
These substances, which can include the protein components in certain foods, dust mites, some types of medication and food preservatives, insect bites and pollens are called allergens, or antigens.
When the immune system detects an allergen, it reacts by producing antibodies, or sending white blood cells to the area to attack the perceived invader. This leads to a chain reaction in the cells, ultimately leading to the release of potent chemicals like histamines.
When the immune system detects an allergen, it reacts by producing antibodies.
An allergy can sometimes just be a cause of irritation, which either resolves itself, or responds to antihistamines.
Typical mild symptoms can include a runny nose, itchy skin, hives, sneezing, a stuffy nose, red or watery eyes, a postnasal drip, or dark circles under the eyes. Allergic reactions can last for anything from a few minutes, to years, such as in the case of eczema or chronic hives (urticaria).
A severe allergic reaction, called anaphylactic shock, needs immediate medical attention. Symptoms includes a raised, red skin rash, swollen eyes, lips, hands and feet, dizziness, swelling of the mouth, tongue and throat, breathing difficulties, wheezing, nausea and vomitting, collapse and unconsciousness.
To control allergies, it’s best to avoid the allergen. If you’re prone to allergies, carry antihistamines with you at all times. Ask your pharmacist for a non-drowsy antihistamine, and see a doctor if your symptoms become severe.
