It is estimated that about fifty million Americans are allergic to one or more things. Our body's immune system produces antibodies when it mistakes any harmless substance or allergen as an intruder. These antibodies are produced to defend the body against the substances mistakenly regarded as offenders. The cells around the affected areas also produce histamine and other chemicals. The release of histamine can result to sneezing, hives, itchiness and other known allergic reactions. These allergic reactions usually appear in areas of the body where the allergen comes to.

Among the most common types of allergies are food allergies, allergic rhinitis, allergic asthma and allergic contact dermatitis. Each of these types has its own specific symptoms and probable form of treatment.

It is estimated that about 100 Americans are killed each year due to food allergies. Studies show that only 1 to 2 percent of all adults with allergies are suffering from true food allergies. The most common food allergens are milk, eggs, fish, peanuts, tree nuts, shellfish, almonds and cashew. It is estimated that about 3 million Americans are allergic to peanuts and tree nuts - the number one causes of food allergy deaths. People suffering from food allergies may experience swelling and tingling of the lips. There may be itchiness, hives or rashes occurring in any part of the body. Additionally, those suffering from food allergies may also feel bloating, abdominal cramps, gas, diarrhea and vomiting.

In severe cases, food allergies can be life threatening. Fortunately, this is rarely the case. If you have known food allergies, the best treatment is to avoid the offending food sources. Otherwise, antihistamines may be administered for mild reactions. Corticosteroid creams may be used to treat skin rashes. For life-threatening reactions, an injectable epinephrine such as EpiPen may save your life. Allergy shots can also be administered especially if drugs don't work, or if you are unable to avoid the allergens.

Allergic rhinitis is a form of allergy which affects one in seven Americans. This form of allergy may occur during a specific season as in hay fever. This can also be perennial, meaning it can be a whole year round condition. Both types however, exhibit similar symptoms. Hay fever is commonly caused by pollen from trees (usually during the spring season), grasses and ragweed. On the other hand, perennial allergies are triggered by indoor allergens like dust mites, feathers, mold spores and pet dander. The most common symptoms of allergic rhinitis are itchiness, watery eyes, sneezing, sore throat and stuffy nose. Allergic rhinitis is commonly treated with antihistamines, decongestants and inflammatory sprays.

Allergic asthma is perceived to be a potentially hazardous disease. Once a person with allergic asthma is exposed to offending allergens, breathing difficulty may commence. This is often elicited by allergens such as pollen, spores, mold, feathers, pet dander and cockroach droppings. Allergic asthma is characterized by coughing, wheezing, tightness of the chest and shortness of breath. Bronchodilators are the treatment of choice during allergic asthma attacks. These function to widen the patient's airways and cease sudden attacks.

Skin contact with allergens like poison ivy, skin care products, jewelries and a person's saliva can trigger allergic contact dermatitis. Common symptoms are itchy, dry, red skin patches with blisters. Corticosteriod creams are used to treat the mild forms of contact dermatitis. Oral corticosteroids may be administered for severe cases.

Finally, allergies affect both children and adults. It is observed that adults hardly ever outgrow their allergies completely. However, the symptoms may become lesser and less severe with time. Others also develop allergies as they grow older. The best defense against allergies is through avoidance of the known allergens.