According to the New York Health Guide, allergic reactions are common. An allergic reaction is the end result of the immune system attempting to fight off an allergen. During the complex reactions in the body, histamine is released in the areas of the body that result in a reaction, such as nasal congestion, hives or asthmatic symptoms. It's the release of histamine that leads to common allergy symptoms, according to HealthMad.com.
Background
Histamine is a chemical found in the human body that assists the immune system in regulating itself. Histamine is needed in the stomach to help process food and helps to defend the body against harmful substances, according to HealthMad.com. It also helps the brain communicate messages and assists in regulating sleeping patterns.
Allergic Reaction
During an allergic reaction, histamine levels sore in the bloodstream, leading to an array of allergy symptoms, according to the American Academy of Allergy, Asthma and Immunology. When someone comes into direct contact with an allergen, the immune system unleashes antibodies, which causes mast cells to produce histamine. Histamine encourages increased blood flow to different areas of the body such as the sinus cavity, the eyes and the lungs. The combination of increased blood flow and high levels of histamines causes common allergy symptoms.
Symptoms
The release of histamines in the body can cause various allergy symptoms, according to the New York Times Health Guide. Upper-respiratory symptoms include nasal congestion, sneezing, nasal discharge, eye and throat irritation. These symptoms can lead to sinus headaches, postnasal drip and coughing. An allergic reaction can also cause an asthma attack, a condition where the airways in the lungs become swollen, making it difficulty to breathe. Skin reactions include hives, rashes and eczema. Talk with an allergist for a proper diagnosis.
Treatment
Take an oral antihistamine on daily to reduce the amount of histamine in the body, according to the New York Times Health Guide. Antihistamines block the mast cells from producing histamine, resulting in a reduction of allergy symptoms. Some antihistamines can cause marked drowsiness and should not be taken if operating machinery.
Considerations
HealthMad.com warns that extremely high levels of histamine can send the body into anaphylactic shock, a rare condition that could be life-threatening. Is someone experiences shortness of breath, a faint pulse and appears to be flushed, call 911 and seek immediate medical attention.
