Allergens are substances which cause the body to react by secreting histamines and other bodily chemicals that cause allergic symptoms like sneezing, runny nose, itching watery eyes, inflammation, pain, shortness of breath, wheezing, anaphylaxis and many others. Almost anything can be an allergen. It is impossible to provide an exhaustive list because the list is so long and almost anything can create allergic symptoms in some people. The list below is one of common allergens in a variety of classifications.
Airborne particles are things that can cause hay fever symptoms, some of these might be; pollens from trees, weeds and flowers. Also included in this category would be mold spores, animal dander, dust mites, perfumes and fragrances.
People can be allergic to medications as well, some of these might be; penicillin (and other antibiotics), sulfa drugs, aspirin (salicylates), local anesthetics (like you might get from the dentist). Also included in this list would be food additives such as nitrites, nitrates (used to preserve deli meats, bacon and hotdogs), msg, sulfites (used as a preservative for fruits, vegetables and in wine). Symptoms from exposure to these items vary but can include breathing difficulties, flushing, nausea and swelling.
Some of the most common food allergens would be; milk, wheat, wheat gluten, corn, corn sweeteners, tree nuts, peanuts (and other legumes), eggs, seafood (especially shellfish), soy, fruits (especially citrus and strawberries) and eggs. Symptoms from food allergies can be hard to pin down since they can take some time to show up. They may cause hay fever symptoms, breathing problems, digestive problems (gas, bloating, diarrhea, and constipation), swelling of the lips and tongue, canker sores, generalized and localized pain and joint swelling.
Reactions to bug and bee stings also needs to be included in the list of allergens. Some people never have problems with bee and wasp stings, still others are extremely allergic and will have a severe reaction to just one sting. Some people never have problems until after having been stung several times and then they have reactions of varied severity. Generally speaking if someone isn’t allergic or not known to be allergic to stings they should be taken to the doctor if stung more than 5 or 6 times. If unable to do that a hot bath can take the poison out of the system. A paste made of baking soda can take the pain out of a sting, as can a vinegar bath. If you know you have a severe reaction to stings it is a good idea to carry an epi-pen to counteract the poison.
This is by no means an exhaustive list of allergens nor is it a complete list of possible symptoms. Every one with allergies reacts differently to allergens and new symptoms can happen at any time. If you suspect that you have allergies or have had severe reactions to specific allergens it is important they you keep a list in your wallet and discuss treatments with your physician.