An allergy, also known as allergic disease, is an immune system response to a foreign substance that is basically not harmful to your body. These foreign substances are generally called allergens. These allergens include certain foods, pet dander, pollen, dust mites, medicines, insect bite, mold spores, etc. Typically, your immune system adjusts to the environment to keep you healthy and fight against harmful invaders such as bacteria or viruses. However, when your body encounters an allergen such as pollen, instead of your immune system realizing that it’s harmless, it perceives it as an outside invader threatening the body. As a result, the immune system then attacks it, thereby responding to a false alarm.

Furthermore, depending on the type of allergen, the response may involve sneezing, inflammation of the skin, sinuses, airway system, digestive system, and many other symptoms. Studies show that genes and the environment play a role in the development of most allergies. Allergies are very common and can affect anyone irrespective of age or gender. It can be mild or severe as anaphylaxis, a type of allergy that tends to be life-threatening. 

Cause of allergies

Anything that comes in contact with your body that is viewed as a harmful foreign substance can cause allergy. When an allergic reaction occurs, allergens bind to immunoglobulin E(IgE), an antibody that your body produces. Antibodies generally are substances in your body that combat foreign and potentially harmful substances in the body. When the allergen binds to IgE, some specific cells will release chemicals that will now trigger allergy symptoms. One of the chemicals produced is histamine, which causes the muscles in the wall of the blood vessels or airways to tighten. Besides that, histamine also commands the lining of your nose to produce more mucus, a major allergy symptom.

Common types and symptoms of allergies 

An allergic reaction generally causes inflammation and irritation. However, allergy symptoms depend on several factors, such as the severity and type of allergy you have. For example, allergy may occur in the eyes, skin, gut, sinuses, or airways.

Below are the major types of allergy and the symptoms they may cause in people;

Allergic rhinitis (hay fever)

Allergic rhinitis is also commonly known as hay fever. It’s usually caused by indoor aeroallergens, and it’s a nasal symptom disease. Allergic rhinitis or hay fever is usually caused by indoor allergens such as animal dander, molds, and dust mites. In addition, grass, trees, or weed pollens can cause seasonal allergies. Most people sometimes have a combination of these two allergies. Its symptoms result from inflammation of tissues that line the inside of your nose( ear or sinuses may also be involved) after exposure to allergens. Common symptoms of allergic rhinitis include;.   

• sneezing
• stuffy or runny nose
• sneezing
• itchy nose, ears, and throat
• watery, red, or swollen eyes (conjunctivitis)

Food allergies

This type of allergy occurs due to a negative reaction of your immune system to certain foods. It may sometimes be difficult to notice that you have a food allergy, which can trigger certain symptoms in your body. Food allergies symptoms include;

• facial swelling
• nausea
• fatigue
• tingling in the mouth
• hives
• anaphylaxis

Skin allergy

Various types of skin allergy including rashes, eczema, burning, burn, hives, contact dermatitis, and many more. It occurs as a result of the abnormal reaction of your immune system to certain allergens. It can happen if you come in contact with what you’re allergic to, such as plants, cleaning products, etc. Although rashes are the most common symptoms of skin allergy, other symptoms include;

• angioedema
• hives
• itchy skin
• burn

Drug allergy

 Any drug can cause an allergy though it’s more common with certain medications. It is the abnormal reaction of your body to certain drugs or complications. This allergy can cause serious reactions and life-threatening complications that affect multiple body systems. Common symptoms of drug allergies include;

• hives
• rashes
• fever
• wheezing
• facial swelling
• anaphylaxis

Treatments

The best way to avoid allergies is to stay away from whatever triggers the reaction, and if that seems impossible, there are other various treatment options available. The treatment of any allergy depends on the severity of the particular condition.

(A) Medications

The common treatment of allergy is through the use of medications like antihistamines to control the allergy symptoms. The medication can either be over-counter or prescription by doctors.

Common allergy drugs include: 

• antihistamines like diphenhydramine (Benadryl)
• corticosteroids
• cetirizine (Zyrtec)
• loratadine (Claritin)
• cromolyn sodium (Gastrocrom)

(B) Immunotherapy

Immunotherapy is also a common treatment of allergies to grass pollens, dust mites, and bee venom. It involves gradually increasing doses of substance or allergen to which you’re allergic. Most people prefer immunotherapy because successful immunotherapy can help prevent symptoms of allergy from returning.

(C) Emergency epinephrine

Epinephrine is the most common treatment for anaphylaxis, and it’s usually administered to prevent the progression of anaphylaxis. If you have a severe, life-threatening allergy, it’s advised to carry an emergency epinephrine shot. The shot helps counter allergic reactions until medical help arrives. Common epinephrine treatment includes EpiPen and Twinject.