Allergies are a common reaction that may stem from environmental or genetic factors, and according to Medline Plus, the normal function of the immune system is to protect against harmful allergens, bacteria and viruses. However, in allergy sufferers, the immune system responds abnormally, releasing histamines, which agitate an allergic reaction. The result is a multitude of symptoms, ranging from mild to severe.
Skin Symptoms
Common substances that cause allergic reactions are environmental irritants like pollen, mold, dust and pet dander. Frequently, these triggers invoke mild symptoms like itching, mucus production (runny nose), headache or swollen eyes, which may be treated with over-the-counter medications like antihistamines and decongestants. However, anaphylaxis can occur in some individuals exposed to allergens like insect venom (bee stings), food products (peanuts or other nuts, shellfish, eggs, milk wheat, soy) or certain medications.
The most common medication that produces anaphylaxis is penicillin, according to Derm Net. Analgesic medications, anesthetics, non-steroid anti-inflammatory drugs (aspirin, ibuprofen or naproxen) and certain types of antibiotics may also cause reactions. Anaphylactic skin reactions are often the first to appear from anaphylaxis, according to the UCB Institute of Allergy. Skin reactions include hives, skin rashes, itchiness, redness and swelling, which are common in nine of ten individuals with anaphylaxis.
Reactions of the Mouth and Throat
While some individuals only develop anaphylactic skin reactions, according to the UCB Institute of Allergy, nearly half of anaphylactic allergy sufferers experience symptoms affecting other organs of the body, such as the mouth and throat. These symptoms are most common in those who have consumed an allergic food and may result in swelling of the lips, tongue or throat; breathing and speech difficulties; trouble swallowing; and itching or tingling in the lips, throat or mouth.
Heart and Blood Vessel Symptoms
Approximately one third of anaphylactic allergy sufferers experience serious reactions affecting the heart and blood vessels. Symptoms include heart palpitations, dizziness, light-headedness and loss of consciousness, which may result from a rapid drop in blood pressure. In some cases, these symptoms lead to cardiac arrest and even death.
Stomach and Intestinal Symptoms
Serious symptoms of anaphylaxis affecting the stomach and intestines include nausea, vomiting and diarrhea, which may affect one third of anaphylactic allergy sufferers.
