Many conditions are caused by an allergic reaction. The most common of these are allergic rhinitis, asthma, atopic dermatitis, and food allergies.
Let's look at each of these in a little more detail.
Allergic rhinitis is the most common allergic condition. It is caused by a reaction to tiny particles found in the air. When breathed in, these normally harmless particles cause the body's immune system to react, release chemicals, and cause swelling and inflammation.
This results in many of the symptoms of allergic rhinitis, including a runny or stuff nose, sneezing, and itching. Symptoms can also affect the eyes, throat, ears, and even sleep.
A second type of allergic condition is asthma. Asthma is a lung condition that affects the ability to breathe by narrowing the airways that move air into and out of. the lungs. Wheezing, chest tightness, and coughing are other common symptoms of asthma.
Many of the same factors that trigger allergic rhinitis can also trigger an asthma attack. In allergic asthma, when the airways come in contact with an allergen, the immune system reacts and releases chemicals. These chemicals cause the muscles around the airways to tighten. Inflammation, swelling, and a build up of mucus in the airways causes further narrowing.
Atopic dermatitis is a third allergic condition. Atopic dermatitis is a type of skin rash. The term "atopic" refers to a tendency to develop allergy conditions, and the term "dermatitis" means swelling of the skin.
Atopic dermatitis is often referred to as eczema, which is a general term for several types of skin inflammation.
People who live in cities and/or dry climates may be more likely to get the condition. Atopic dermatitis usually develops in early childhood and continues into the teen years, but it can affect people of all ages.
Atopic dermatitis symptoms include:
• Sensitive skin
• Extremely itchy skin
• Patches of red, dry skin
• A rash that appears wet
• Blisters or thickening of the skin.
A fourth type of allergic condition is food allergies. A food allergy is a reaction to one or more normally harmless proteins found in the offending food. The body's immune system reacts to this normally harmless protein or proteins and releases chemicals.
An allergic reaction to food can take place from within a few minutes up to several hours after the food is eaten.
The symptoms will depend on where the reaction occurs. For example, if the reaction occurs within the mouth, itching of the mouth and swelling of the lips and throat can occur. If the reaction is within the digestive tract, nausea and vomiting are common. Food allergies can also cause more serious or life-threatening problems.
Many types of food can cause an allergic reaction. In children, eggs, milk, peanuts, soy, and wheat are the main culprits. The most common foods to cause allergies in adults are:
• Shrimp, lobster, crab, and other shellfish
• Walnuts and other tree nuts