Allergy or allergic reaction is a condition occurring due to an overreaction of the immune system of the body to certain otherwise harmless foreign substances. The immune system of the body normally protects us from harmful foreign substances called antigens like disease causing pathogens, abnormal harmful substances in the body, etc. by producing antibodies. Antibodies target the foreign substance and destroy it with the help of the defense mechanisms of the body. In some cases, antibodies are produced against substances, called allergens, which are not inherently harmful to the body. Antibodies against allergens trigger a massive overreaction of the immune system which causes harm to the body, and may even cause death.
Allergies occur when substances called allergens are wrongly recognized by the body to be harmful due to a genetic predisposition. Allergens can be almost anything, including pollen, dust mites, some types of food, insect bites, animal hair, some plants, medications, some viruses and bacteria, as well as changes in temperature, stress, etc. Antibodies against allergens produce a diverse array of reactions by facilitating the body to release certain chemicals called mediators, histamine being a common example. Reactions may be localized rashes, uncontrollable sneezing, hives, difficulty in breathing, or may be systemic involving the whole body. In severe cases allergy can cause a massive reaction called anaphylactic shock which may even be fatal.
Allergy has no definite treatment. Various different modes of treatment exist and have different levels of effect on different people. Avoiding the allergens combined with immunosuppressants has so far been the most successful in keeping the condition under control.
Treatment for allergy is based mostly on avoiding the allergens. In absence of allergens, antihistamines form the medicine of choice for allergy. Antihistamines are prescribed to target the mediator histamine and are useful to treat long term allergic reactions like rhinitis. For severe reactions, epinephrine is injected to counter anaphylactic shock by dilating the bronchii and increasing blood pressure. Corticosteroids are administered through intravenous tube to counter the more severe allergic reactions including inflammation. Corticosteroids can be applied as topical ointment to tackle allergic reactions of the skin, or may also be used as nasal sprays to reduce symptoms of stuffy or blocked nose. Epinephrine is used as an emergency treatment to reverse the effects of an allergic reaction. Both over the counter and prescription medications are available to treat an allergic reaction. Another treatment method used to treat mild allergies is allergy shots, where the patient is exposed to allergens in progressively higher doses over a period of time starting with a very low dose. This procedure sensitizes the immune system to that allergen so that it does not produce an allergic reaction.
Allergies can occur anytime, and allergens that trigger severe response in some may not trigger a response of similar intensity in others. In most cases, a mild reaction goes away once the allergen is removed from the vicinity. However, it is advisable to undergo treatment if symptoms of allergic reaction appear, especially if there has been a severe allergic reaction in the past. If symptoms worsen or persist even after removal of allergens, treatment needs to be started immediately.
Mild reactions usually go away on their own once the allergens are removed and treatment is not required. However, it is advisable to undergo treatment even if the symptoms are mild as an allergy can progress from mild to fatal in a very short time.
Treatment procedures for allergy may have a small side effect of suppressing the immune system, making a person vulnerable to other small infections.
Post treatment guidelines include avoiding the allergens that causes a reaction, like pollen, allergenic food, dust, animal hair, etc.
There is no fixed period for recovery from allergies. Some people get better within a few hours after the allergens are removed, while some people may need extensive long term treatment to recover.
Price of treatment starts from as low as Rs. 50 and goes up to Rs. 5000 or higher for long term treatments.
Allergy is incurable and treatment is targeted towards reducing the symptoms. Once treated, results are permanent till the next exposure to the allergens.
Alternative treatment options for allergy include allergy shots, herbal medications, and also acupuncture. These treatment methods vary greatly in their efficacy and may be used along with the standard modes of treatment.