What is Allergic Reaction?

An allergic reaction is the body’s response to a foreign substance that comes in contact with the body through the skin, air or by oral consumption. The body’s immune system responds when it detects a foreign substance, known as antigen. This reaction to the allergen is an allergic reaction.

Mechanism of an allergic reaction

Upon detecting the antigen, the body’s immune system comprising the white blood cells produces antibodies specific to that antigen. This is the process of sensitization. This antibody is usually Ig E and it stimulates the production of hormones or mediators like histamines.These mediators further lead to activation of more white blood cells, resulting in the signs of an allergic reaction. The next time this allergen comes in contact with the person, it will result in an allergic reaction or hypersensitivity.If this response is sudden, the allergic reaction can be severe and life threatening.

Types of allergens

Common allergens include pollen, dust, foods , latex, certain types of medicines, aspirin, animal dander, and insect bites and bee stings. Some people are genetically pre-disposed to certain allergies.Others with asthma,sensitive skin , frequent respiratory tract infections are more likely to have an allergic reaction.

Symptoms of an allergic reaction

  • The allergic reaction can be mild, moderate or severe. Mild to moderate allergic reactions are easy to control while severe reactions may need hospitalization.
  • Hives ,rashes, redness over the affected area and inflammation .
  • Running nose and stuffiness, sneezing.
  • The eyes itch and water continuously. The person may have a headache, difficulty in breathing, tightness in the chest, dizziness , nausea and diarrhea.

A severe reaction is termed anaphylaxis. The person gasps for breath, there is an increase in the heart rate and the blood pressure dips rapidly. The throat becomes dry and the person goes in to shock. It leads to cardiac arrest and even death.Call an ambulance immediately and get quick medical help to save the person’s life.

How to treat an allergic reaction

The treatment depends on the intensity of the allergic reaction. For a mild to moderate reaction, first identify the allergen and remove it immediately from the affected person’s vicinity. Next calm the person and apply calamine lotion over the itchy area. A cold compress gives relief from itching. Remove the venom of a sting with a fingernail but not tweezers. Monitor the person for sometime for worsening symptoms. Anti- histamines can help relieve some of the symptoms like runny nose and itching.A topical steroid ointment can help relieve inflammation and itchiness.

In case of a severe reaction, take steps to avoid shock.Give him an emergency injection if he so says, but avoid oral medication as it may result in choking. Rush him to the hospital where the doctor may administer an epinephrine injection

Detecting an allergic reaction

The doctor will take your pulse rate and blood pressure. He will physically examine you for signs of rash or inflammation. He will question you on any known allergies or your recent food intake and then prescribe the required medicines.

However prevention is the best cure and it is advisable to avoid the allergen to protect yourself from an allergic reaction. Since the consequences of an allergic reaciotn can be fatal, learn to recognize the symptoms and seek medial help immediately.