Allergy symptoms are the result of your body attacking a normally harmless protein. In order to fight off the protein (called an allergen), your body will release specific antibodies called Immunoglobulin (IgE). The IgE causes histamine to be released; your body’s response to the histamine is what causes allergy symptoms.
You can be allergic to almost anything, from pets to food to pollen to insect stings. Your allergy symptoms depend entirely on what you are allergic to, how severe and how you come into contact with the allergy.
There are eight foods that make up 90% of all food allergies: eggs, milk, peanuts, tree nuts, fish, shellfish, wheat and soy. Typically, the symptoms of a food allergy are vomiting, hives, shortness of breath and trouble swallowing. A life-threatening reaction called anaphylaxis can also occur. An anaphylaxis reaction can include trouble breathing, reduced blood pressure and vomiting. The only treatment for these symptoms is an injection of epinephrine. The treatment for less severe reactions is an antihistamine, such as Zyrtec or Benadryl.
Seasonal allergies, technically called allergic rhinitis or hay fever, are typically caused by allergies to airborne mold spores and pollens from grass, trees and weeds. A runny nose, itchy eyes, sneezing, stuffy nose and fatigue are the most common symptoms of seasonal allergies. Simple home remedies such as keeping the windows closed or using dust mite-proof bedding should be the first line of deference. Decongestants and antihistamines are recommended if you are still experiencing symptoms.
Pet allergies, specifically to dogs and cats, are triggered by the proteins in their dander, saliva and urine. These proteins can cause sneezing, runny nose, nasal congestion, coughing, red and watery eyes and a skin rash. To prevent these symptoms, always wash your hands after touching an animal and keep pets out of your bedroom. Nasal symptoms can then be treated with steroid nasal sprays or antihistamines and the eye symptoms can be treated with antihistamine eye drops.
An allergy to insect stings can be very unpredictable. The venom from five insects— honeybees, hornets, wasps, yellow jackets and fire ants—is known to cause allergic reactions. The severity of a reaction can vary from one sting to the next and from person to person; just because you had a mild reaction last time does not mean the next one won’t be life threatening. There are three categories of reactions that can occur: normal local, large local and a systemic allergic reaction. A normal local reaction results in swelling, redness and pain at the site of the sting. In a large local reaction, the swelling will go beyond the site of the sting and can last for up to a week after. A systemic allergic reaction can range from mild to severe and can include hives, itching, redness, swelling, dizziness, vomiting, unconsciousness and cardiac arrest. The most severe of these reactions is an anaphylaxis reaction. The only treatment option for this life-threatening reaction is a dose of epinephrine. The less severe reactions can be treated with antihistamine.