What are allergies and who suffers from them?
Allergies involve an immune response in the body to things such as plant pollen, other grasses and weeds, certain foods, rubber latex, insect bites, or certain drugs. Estimates suggest that allergies affect more than 50 million people in the United States. Nearly 10% of American women have pollen allergies. Allergic drug reactions, commonly caused by antibiotics such as penicillin, occur in 2%-3% of hospitalized patients. Severe allergic reaction to insect stings occurs in up to 5% of the population. Although most people have experienced a reaction to something they have eaten, only 1% of the adult population suffers from true immune reactions to food.

What is an allergic reaction?
Normally, the immune system is the body's defense against invading agents such as bacteria and viruses. In most allergic reactions, however, the immune system is responding to a false alarm. When an allergic person first comes into contact with an allergen, the immune system treats the allergen as an invader and mobilizes to attack. The immune system does this by generating large amounts of one type of antibody. When the allergen and the antibody connect, it signals the release of powerful inflammatory chemicals. These chemicals, like histamines, cytokines, and leukotrienes, act on the tissues of various parts of the body, such as the respiratory system. The result is the symptoms commonly associated with allergies.

What symptoms are associated with allergies?

• Common symptoms for allergies include:
• Sneezing, often accompanied by a runny or clogged nose
• Coughing and postnasal drip
• Itching eyes, nose, and throat
• Watering eyes
• Allergic dermatitis: an itchy rash. (The most common skin condition in children ages 11- 14.)
• Allergic shiners: dark circles under the eyes caused by increased blood flow near the sinuses
• Allergic salute: persistent upward rubbing of the nose that causes a crease mark on the nose
• Conjunctivitis: an inflammation of the membrane that lines the eyelids, causing red-rimmed, swollen eyes, and crusting of the eyelids. Commonly known as pink eye.

Some people with allergies develop asthma. The symptoms of asthma include coughing, wheezing, and shortness of breath due to a narrowing of the bronchial passages (airways) in the lungs, and to excess mucus production and inflammation. Asthma can be disabling and sometimes can be fatal. If wheezing and shortness of breath accompany allergy symptoms, it is a signal that the bronchial tubes also have become involved, indicating the need for medical attention. Some people may have severe food allergies which left undiagnosed can result in illness or in rare cases, may even be fatal.

Does asthma affect women differently than men?
From the ages of 20 to 50, women outnumber men 3 to 1 in asthma-related hospital admissions. There is some evidence that asthma may be related to hormonal changes in combination with an allergic setting. The severity of asthma may change for women during pregnancy. In general, symptoms in pregnant women with asthma seem to improve in one-third of cases, stay the same in one-third, and worsen in one-third of cases.

Most women who have asthma are able to have safe and normal pregnancies as long as their asthma is effectively under control. It is extremely important for women to control their asthma while pregnant because asthma causes a decrease in the oxygen in the blood and can affect the amount of oxygen the fetus receives.

What are the most common allergies?
The most common allergies can be either food allergies or airborne allergies. Airborne allergies include reaction due to pollen, mold, dust mites, animals, and chemicals. The most common foods causing allergic reactions in adults are: shellfish (such as shrimp, crayfish, lobster, and crab); peanuts, which are one of the chief foods to cause severe anaphylactic reactions; tree nuts (such as walnuts); fish; and eggs. In children, the most common food allergies are associated with eggs, milk, and peanuts. Adults generally don't lose food allergies, but children may outgrow them.

What are hives?
Each year about 15% of all Americans experience hives on the skin or angioedema (swelling of the throat tissues) due to allergic reactions. Hives are an allergic reaction often due to food or plants. The reaction is characterized by a raised, itchy area of skin. It can be rounded or flat-topped, but it is always elevated above the surrounding skin. Treatment for hives usually involves identifying and avoiding the allergic catalyst. Anti-histamine over-the-counter medications can help temporarily relieve the itch. Hives can disappear as quickly as it appears.

How are allergies diagnosed?
Allergy symptoms often resemble a cold, however the cold seems to linger. Symptoms include a runny nose, itchy eyes, headaches, and sinus pain. Usually there is no fever. It is important to see a doctor about any respiratory symptoms that last longer than a week or two. Properly trained physicians can recognize patterns of potential allergens. Often skin tests or blood tests are used to determine specific antibody levels reacting to a certain allergen. If there are unusually high levels of an antibody known as IgE, it is a good indication of an allergic reaction.

How can allergies be treated? What are the possible side effects from treatment?
Allergies are usually treated in three possible ways. Some of these methods can be used alone or in combination.

Avoidance: This is most effective for food allergies. Once the allergen is identified, it can be avoided simply by removing it from the diet. Avoidance is more difficult for airborne allergens, however, which are often associated with a particular climate and environment.

Medications: Several oral antihistamine medications are available over-the-counter or by a doctor's prescription. A combination of antihistamines and nasal steroids can effectively treat allergic symptoms, especially in people with moderate or severe allergic symptoms. Oral and nasal decongestants reduce congestion sometimes caused by the allergic reaction. However, most medications are for short-term relief only. Nose drops and sprays should not be used for more than a few days at a time because they can lead to even more congestion and swelling of the nasal passages. If you find you "can’t get through the day" without regular use of nasal sprays - see your doctor, and if you can, an allergy specialist. (For example, an ear, nose, and throat doctor.)

Immunotherapy: This is series of allergy shots, and is the only available treatment that has a chance of reducing allergy symptoms over the long term. About 80 percent of people with hay fever will have a significant reduction in their symptoms and in their need for medication within 12 months of starting allergy shots.

Does breastfeeding effect a baby’s allergic responses?
Exclusive breast-feeding (excluding all other foods) of infants for the first 6 to 12 months of life is often suggested to avoid milk or soy allergies from developing within that time frame. Such breast feeding often allows parents to avoid infant-feeding problems, especially if the parents are allergic (and the infant therefore is likely to be allergic). There are some children, who are so sensitive to a certain food, however, that if the food is eaten by the mother, sufficient quantities enter the breast milk to cause a food reaction in the child. Mothers must themselves sometimes avoid eating those foods. However, there is no conclusive evidence that breast-feeding prevents the development of allergies later in life.