According to Medline Plus, an allergy is an immune system reaction to a substance that doesn't affect the general public. More than 30 million people suffer from allergies in the United States, according to the American Academy of Allergy, Asthma and Immunology. MayoClinic.com states that most allergies are caused by foods and airborne substances such as pollen and medications. No matter the type of allergy, most allergy reactions have similar signs and symptoms.
Cause
Kids Health states that an allergic reaction is an overreaction of the immune system that causes common signs and symptoms of allergies. Once the immune system identifies a particular substance as an invader, it releases specific antibodies to fight off the substance. The antibodies start a chain reaction in the body that releases histamine into the blood. Histamine is the chemical responsible for allergy symptoms.
Symptoms
According to AAAAI, a common allergy symptom is nasal complications. Nasal complications include nasal congestion, postnasal drip, a runny nose and excessive sneezing. Nasal congestion is the result of the sinus cavity becoming inflamed and swollen. Inflamed sinuses can cause excessive pressure around the nasal cavity resulting in an earache, toothache or headaches.
Asthmatic reactions are a common sign and symptom of allergies, according to MayoClinic.com. When histamine is released into the bloodstream it can cause the airways to tighten and become inflamed. Someone with allergy-induced asthma experiences shortness of breath, wheezing and chest pain. If the individual becomes lightheaded or severely dizzy, she should seek medical attention.
Treatments
According to MayoClinic.com, the most common treatment for allergy symptoms is antihistamines. Antihistamines are sold over-the-counter and work by blocking the body's ability to produce histamine which causes common allergic reaction symptoms. Allergy shots are another treatment for severe allergy symptoms.
Triggers
Medline Plus states that common triggers for allergy signs and symptoms are environmental allergens, food allergens and household allergens. Environmental allergens are pollen and mold that affect most people during spring when plant life is blooming. The most common food allergies are nuts, dairy and egg allergies. Household allergens include cockroaches, dust mites and pet dander.
Complications
Kids Health states that allergy signs and symptoms include eye and throat irritation. The eyes become watery, itchy and red which can lead to allergic conjunctivitis. Postnasal drip can complicate an itchy throat with a constant dripping of mucus. This can cause a sore throat and chronic coughing.
