The Origin of Allergic Reactions
An allergic reaction results basically by the interaction of two things – the allergy causing agent, which is known as allergen, and the human being who is the allergy victim. Lots of things in nature are potential allergens, based upon the human immune system’s response to it.
Every cell in the human body has a unique trade mark to it. Body’ immune system recognizes that trade mark. It gets suspicious of any particle like a bacteria or virus in the body that does not carry that trade mark and considers it an unwelcome interference that has to be removed. It is because of this propensity that body tends to reject a transplanted organ. Allergy is a miniature form of this organ rejection.
To attack an object that it recognizes as a foreign body, white blood cells travel towards that object. In the case of an allergy attack, what the white blood cells recognize as enemy are generally certain proteins. Proteins in certain foods or pollen grains are recognized as foreign objects by the immune system of some people. Their white blood cells release enzymes and histamines to cover the enemy object, starting an allergic reaction.
While the basic principle of identifying a foreign object is the same in everybody’s body, in the case of those prone to allergies, the immune system overreacts. The system produces too much of histamines and the like. This is what translates in human beings as allergy symptoms like itching, swelling, or watery eyes.
While this allergy response, or reaction of the immune system, can vary from individual to individual, it can also vary in the same individual over a period of time. For example, consider the case of an individual who is constantly exposed to dust. In the normal course of events, he may not show any allergy symptoms, because the harmful part of it is generally filtered out by the body. But the dust mites in the dust may leave its proteins in his system so that after continuous exposure, he may become extra sensitive to it, leading to stronger allergic reactions.
Genes definitely seem to have some role in making a person prone to allergy because it is often found to be an inherited trait. However, there could be environmental factors also that play a catalytic role in inducing allergic reactions. A breastfed baby, for example, is seen to be less prone to allergy even in a family more prone to allergy.
A new born infant does not generally have a strong immune system. It gets the necessary antibodies from its mother through breast milk and colostrum (the milk produced by the mother for a few days after giving birth).
Since babies produce very little stomach acid, the antibody proteins are not destroyed by their stomach acid. So the proteins, and peptide hormones like prolactin absorbed through breast milk, survive in the infant’s system. Further, proteins that help the immune system are glycosylated. That too protects them from breaking down. All these make babies less prone to allergy.
It needs a lot more study on the functioning of the immune system to be able to pinpoint what exactly triggers allergic reactions and how to control allergy symptoms.
Do You Think You Have An Allergy? Confirm It By Correct Diagnosis
There are various symptoms of a running nose or red marks on your skin. You need to get proper consultation to decide if it is due to any allergic reaction/s. It can be diagnosed by performing some methods like skin test or blood test.
Tests That Confirm Allergy
Skin test or prick tests are the most common tests for detecting allergies. For performing this test you need a small quantity of allergen, a non parasitic antigen or alternatively a solution of dander. A dander is a material containing scales of dried skin and hair, or feathers of animals. These items are injected into the skin. It is recommended that you stop all regular medicines including Benadryl, Claritin for a given period, while tests are being conducted, to get better results. In case you are taking antihistamine, Allergen (fexofenadine) then you are, required to perform these tests after a week of discontinuation of the medicine.
The doctor may put the patient through some other skin tests for diagnosis also.
Percutaneous test In this process few drops of the non parasitic antigen, allergen are pricked near the surface of the skin. This test is used to diagnose allergic sensitivity towards pollen or dust mite waste or mold or animal dander etc.
Intracutaneous test The process is done by injecting the allergen into the skin at a more deep level than the Percutaneous test. Allergies arising due to bee venom or wasp venom or from penicillin antibiotics can be detected by this method.
Epicutaneous test An allergen patch is applied on the skin for certain duration. A patch test helps to detect skin allergies caused due to sensitivity of skin to perfumes. It also arises due to preservatives or chemical reactions of hair dyes on the skin. This is known as contact dermatitis. The doctor then studies the reaction on the skin and medicates him accordingly.
The tests are carried out on the forearm for the adults and on the upper portion of the back in case of children. The injections and the tests given to detect the allergies are not at all painful. A person may suffer a little uneasiness if he is allergic. The tests help the doctors to bring out the allergic reactions of the skin. The most common allergy symptoms are itching, swelling and redness of the skin. The doctor must know the medical history of the patient. The allergist guides the patients regarding the type of test to be done. This helps the doctor to know harsh reactions or anaphylaxis that the patient may suffer from during the tests.
Blood Tests for Allergic reactions
Blood tests are costly but less accurate than skin tests. However, it is recommended for people who have a sensitive skin and skin test cannot be performed on them. A little quantity of blood is taken from the patient’s body to carry out this test. In this process the percent of IgE (immunoglobulin) present in the blood is measured.
Mostly people suffer from mild allergy. These mild allergies are continual and need to be cured by proper tests and medication.
Avoid Allergies: Use Home Purifiers to Minimize the Allergens.
Allergens are the non parasitic antigens. A good way to avoid allergy symptoms in people is by minimizing the number of the allergy causing products. An air purifier fitted at home or in the car helps to reduce the allergies. Allergic reactions arising due to allergy product which are air borne, can be kept away by using home purifiers.
We may come across different varieties of air purifiers in the market. The effectiveness one purifies differs from the other purifier.
Ozone or trioxygen (O3) is a triatomic molecule, consisting of three oxygen atoms. The molecules of oxygen are steady and they destroy the third atom of oxygen. This situation gives out unpaired atoms or ions which have electrical charge. Some home purifiers also create ozone.
The charged oxygen particles have adverse effects on the lungs. Since they are oxygen molecules and have energy in them, they give rise to chemical reactions on the body. A person may also suffer from skin or lungs cancer in harsh situations. Asthma symptoms become worse in people when they are exposed to big amount of ozone.
A sensitive person can even trace the ozone present in the air by smelling it. A standard home purifier forms less amount of ozone than the danger mark. The main intention of using it in the air purifiers is to mix with the allergy products which contain harmful particles and purify the air.
The home air purifiers have metal plates in it. They work by producing less intense electric charge on the metal plates. The dust particles and the extracts from animal skin or hair or other particles which give rise to allergic reactions are attracted on the plates with the use of fan fitted in the purifier. The plates should be cleaned every week.
Use of purifiers considerably minimizes the dust particles, smoke and other allergy products. The allergic reactions can be avoided, if a proper sized home air purifier is used. A large room will require a big purifier than a smaller room.
Good quality home air purifier has a HEPA filter in it. The HEPA filters attract the dust particles and the allergy products present in the air on the plates by charging them and hold them permanently instead of releasing them in air.
The prices of the home air purifiers vary in the markets. The costly purifier may not necessarily have a HEPA filter in it. The life of the purifiers is usually between three to ten years. Some of them can be washed and cleaned. Some other home purifiers can be used only for a year or two.
While selecting a purifier, one should also consider the noise generated by the air purifier. A good quality air purifier works in complete silence.
The home air conditioner or a heating device should necessarily have a good quality filter. This helps in reducing the dust particles and other allergy products from the air. The areas like bedrooms and offices where we spend most of our time, can be cleaned effectively by using home purifying device.
Are You Dust Mite Sensitive ? Here Are A Few Ways to Prevent Allergic Reactions.
The allergic reactions are mostly caused by the dust mites. Dust mites are found everywhere. Sensitive people are allergic to the dust mites. Dust is not a non parasitic antigen and hence not responsible for allergic reactions.
The bodies of the dust mites decompose and waste products from them are produced. They launch the proteins in the surroundings. Antibodies are the proteins in our blood and are used by our immune system to identify the foreign particles like bacteria and virus. Antibodies are also called IgE (immunoglobulin E). The IgE increases the release of histamines. Itching and watering of eyes (conjunctivitis), running nose (allergic rhinitis or hay fever) are few allergy symptoms which arise due to the histamines.
Melting of snow and rains increases the humidity in the air. The population of the dust mites rises during the winter and they perish, when the humidity level is less than 50%.
Proper prevention can help in reducing the dust mite sensitivity. The few precautions can be taken to avoid the allergy.
Cleaning at regular intervals can reduce the number of dust mites. Woolen beddings may be comfortable, but they hold major number of dust mites. The bed spreads and sheets should be washed with warm water every week. Hypo-allergenic bed sheets and freeze dry beds can help people with this allergy. Alternatively, synthetic bed sheets can help the sensitive people.
Children having a family history of allergy may be more prone to dust mites. Warm water can be used to clean their pillow covers. Soft toys washable with hot water may be given to the children.
Dust mites are weighty and they do not remain in the air for a long period. Vaccum Cleaners with a good HEPA filter may be used to clean the house. Special dusters and mops that collect the dust within them are available in the markets. A mask used during the dusting process is of great help. It is advisable to enter the room after an hour. This allows the dust to settle down.
Wood or artificial flooring may be used as they can be cleaned easily. They hold less dust than the carpet floorings. Shutters made of wood or plastic and louvers are easy to maintain.
Medication is the best way to cure allergy symptoms. Medicines are to be taken as prescribed by the doctor. Overdoses of medicine can have an adverse effect on the patient’s health. Antihistamines such Benadryl (diphenhydramine), Claritin (loratadine) and nasal sprays like Nasonex may provide relief to the patient.
Bronchodilator helps in opening the bronchial tube. This allergy treatment is helpful to patients suffering from asthma like wheezing and constant cough. Consulting the doctor before taking medicines is very important. Even corticosteroids or a combination of it can be taken.
Immunotherapy is mostly used in extreme cases. It is a long term allergy treatment and should be carried as per the doctor’s advice. In this process allergy injections having the extracts of dust mites are used. They help in desensitizing the patients.
Allergy Treatment by Immunotherapy
Allergy is, in reality, no disease at all. It is body’s defense mechanism, or immune system, going on overdrive. However, allergy is an irritating condition that requires immediate control, and antihistamines are often used in allergy treatment. Some of the medicines used are Claritin (loratadine), Benadryl (diphenhydramine) and decongestant sprays like Nasonex. But these cure only allergy symptoms. To affect a lasting cure, we should aim at preventing allergy by dealing with the body’s immune system.
Allergies can be prevented by allergy immunotherapy. The procedure consists of weekly injections. The medicine that is injected is calculated doses of allergens like pollen extracts, or cat dander extracts. These may sometime be genetically modified to increase the efficacy. Allergy is immune system’s overreaction to a foreign substance. So, the therapy tries to desensitize the immune system by familiarizing it with objects that it perceives as enemies.
This form of allergy treatment has been in use for quite sometime though it has some drawbacks.
The first snag is the slightly prohibitive cost of allergy immunotherapy, since a trained professional is needed to administer it. It is costlier than over the counter medications and even prescription medicines.
Further, this form of allergy treatment is a time-consuming process. Getting the correct dosage of the medicine itself will take time and may require several visits to the doctor. And even after the decision making process is over, the actual allergy treatment would go on for anything from three to five years. The process is aimed at changing the perceptions of the immune system of the patient, and it has to be a gradual process. The duration of the treatment will vary from person to person based on the result.
And allergy immunotherapy is not effective in the case of certain types of allergies like food allergy. The treatment procedure involves inducing allergic reactions by the medicine that is injected. There is an element of risk in it and when it is done to prevent food allergy, the risk of anaphylaxis is stronger. It could easily lead to a dangerously bad situation of allergic reaction.
However, researches conducted on the efficacy of allergy immunotherapy, and the clinical data available on it, paints a satisfactory picture. This form of allergy treatment works well for many people. About 75% of the people who submit themselves to long term allergy immunotherapy have been completely cured of their allergy problems. For the rest of them, even though there was no complete cure, there was conspicuous decrease in allergy symptoms.
Getting shots for allergy is mainly effective for allergy resulting from pollen dust, animal dander, and dust mite waste. Shots also minimize allergic reactions due to stings from a bee or a wasp. It was also found to be effective in controlling hay fever and asthma. Allergy immunotherapy has worked for many who do not respond to other types of allergy treatment like over the counter, or prescription medicine.
For those, who have severe allergy symptoms, and those who are apathetic to being on a daily pill regimen, the existence of allergy immunotherapy is good tidings.
Allergy and the Hyperactive Immune System
Allergic reactions occur as a result of the human immune system’s efforts to protect the body. Many of the allergy symptoms like a running nose, or a swollen lip, or an upset stomach, are manifestations of over-cautiousness on the part of the human body.
Simply put, allergy is over-sensitivity. There are all sorts of things in the atmosphere which become potential allergens to those who are prone to allergy, while they do no harm to others. That simply means that those who are prone to allergy have a hyperactive immune system.
Human body contains a system known as lymphatic system made up of lymph nodes and lymph ducts. It carries a fluid known as lymph, the way circulatory system carries blood. The lymphocytes, which the lymph nodes produce, play an important role in body’s disease preventing mechanism and so in causing allergic reactions.
Many organs like appendix, tonsils, bone marrow, and the thymus gland that lies underneath the breastbone, contains lymphoid tissue. It is in the thymus gland that a certain variety of white blood cells, known as T cells, are produced. These T cells are also an important agent in causing allergy symptoms.
Lymph nodes and T cells might have become familiar words for many these days, because of its association with AIDS. But everybody is not aware of its connection with allergy.
Every cell in a human body has a unique code that is exclusive to that body. When T cells and lymphocytes pass through the lymphatic vessels and blood vessels, they easily detect a foreign particle, a bacteria or a virus, that has a different code. Some of these really require removal. But allergy symptoms erupt when they identify as enemies even those things that do not require instant removal.
Some T cells only identify the foreign bodies. The removal is generally managed by phagocytes. Some other T cells do the job together with B cells. Yet other T cells directly combat the particles that they identify as worthy of removal. This could be the beginning of an allergy attack.
Once a foreign particle has been identified, certain groups of white blood cells known as mast cells, and basophils, release chemicals like prostaglandins and histamines in the area to remove the invading particle. These chemicals are supposed to neutralize the enemy and remove it. The process is necessary when the invading particle is harmful to the body.
Sometimes this attack is unleashed against harmless objects also and it is these that we see as allergic reactions. The larger the unnecessary reaction, the more is the amount of the histamines released. The allergy symptoms will be more severe in such cases.
Allergy is, in short, a wound that body inflicts on itself. The nasal inflammation resulting from allergic rhinitis, conjunctivitis, and hives are all examples of this attempt of the body’s self protection becoming counterproductive and becoming allergy symptoms.
A strong immune system is body’s requirement. But an immune system that could be stronger than necessary is what causes allergy. To avoid allergic reactions and at the same time have the required protection against real invaders, we must have a balanced immune system.
Allergy Symptoms as Hives
Hives is a common form of allergy characterized by itchy red rashes on the skin. It is known as allergic urticaria in medical terminology and many things can produce the type of allergic reaction characterized by hives.
Food allergy is one of the main causes that can lead to hives. Many people develop allergic reactions by having shellfish, milk, eggs, or peanuts. Scratching is what causes complications with hives because itchiness is the main problem in this type of allergic reactions as the bumps are hardly painful.
Hives may result from the administration of penicillin or other antibiotic drugs as many of these can give rise to allergic reactions in people. Other medicines that can form the cause of allergy are ibuprofen, aspirin etc.
Hives is seen in people as a result of contact with pollen or animal dander. Insect stings or bites from a bee or a wasp or a spider can also result in allergy. Severe allergic reaction in such cases can even lead to breathing difficulty. Anyway, even those who have mild allergy symptoms would show the red bumps characteristic of hives.
Any potential allergens that can cause allergic reactions in human beings can lead to hives as well. Conjunctivitis, allergic rhinitis, hay fever etc. have typical allergy symptoms which are hives. The similarity here is that all of these result from the production of excess histamines and cytokines. This is what causes swelling.
How to control hives
For allergy, prophylactic measures are better than treatment, as much as possible. Keep the home and surrounding clean to avoid insects or prevent things like mold growth. When allergy symptoms appear, they can be controlled a lot, but there is no lasting cure for allergy.
A cold compress would help to quell some of the allergy symptoms like swelling and itching. A cold shower also may work sometimes. Scratching has to be avoided since it would worsen the allergy symptoms by bruising the area.
Over the counter medicines like Claritin (loratadine) and Benadryl (diphenhydramine) are effective in combating allergy symptoms. Benadryl tends to make the user a little drowsy while Claritin does not. Common prescription drugs used in allergy control are Allegra (fexofenadine) and Atarax (hydroxyzine). When allergy symptoms are severe doctors may prescribe any oral corticosteroid.
Red bumps or rashes may sometimes be a skin problem and not a case of allergy. Professional help may sometimes be necessary for diagnosis, though those who have been subject to allergic reactions before may be able to make out the difference. Hives can also be similar in appearance to contact dermatitis which results from the skin coming into contact with the oil of poison ivy.
Allergic reactions in human beings are believed to be controlled by genetic factors to a certain extent as allergy problems are found to run in families. Individual sensitivities, however, vary. Those, who are too easily prone to allergic reactions, should ideally keep with them auto-injectors like EpiPen, with which they can self-administer advised doses of epinephrine. It helps to temporarily control allergy symptoms and prevent extreme problems like anaphylactic shock.