Allergies are atypical reactions of the immune system that occur in response to otherwise harmless substances. Allergy is the most widespread disease in the world. The immune system responds to foreign microbes or particles by producing some proteins called antibodies. These antibodies are able to bind to identifying molecules, or antigens present on the foreign particle. This reaction between antibody and antigen sets off a series of chemical reactions intended to protect the body from infection.
Sometimes, this same series of reactions is triggered by harmless, everyday substances such as pollens, dust, and animal dander (loose scales of skin shed from the body of animals or from feathers). When this occurs, an allergy develops against the offending substance called the “allergen”. So an allergen is the substance that provokes allergy.
1. Air borne allergens:
- Animal fur and dander
- Body parts from house mites
- Plant pollens
- House dust
- Cigarette smoke
- Mold spores
- Microbes etc.
2. Food allergens:
- Cow’s milk
- Fish etc.
3. Medication allergens:
- Penicillin and other antibiotics
- Flu vaccines
- Tetanus vaccine
- Gamma globulin
4. Insects and arthropods:
- Bees , wasps, hornets
5. Contact dermatitis allergens:
- Nickel alloys
- poison ivy, oak, sumac
SYMPTOMS OF ALLERGIES
Symptoms of air borne allergies:
The dust, pollens, smoke, pet fur and dander may cause a slight to severe coughing and sneezing in mild cases but in extreme conditions it can cause dangerous breathing problems such as bronchitis and asthmatic attack.
Symptoms of food allergies:
Continuous wheezing and stomach pain along with nausea vomiting is the major symptom of food allergy. Eczema, bronchitis and asthma like symptoms can also be seen.
Symptoms of medication allergy:
The drugs or antibiotics cause severe skin rashes or hives along with itchy skin, swelling of body parts and severe conditions like anaphylaxis.
Symptoms of allergy due to insect sting and bites:
Harsh conditions may show symptoms of anaphylaxis, breathing problems and hives. Swelling at the site of attack is one of the most common symptom along with this dizziness, unconsciousness, swelling of tongue and cardiac attack are the signs which happens in severe conditions.
Symptoms of contact dermatitis:
The symptoms include itchy red skin, small bumps which are filled with fluid which oozes out .Sometimes various blisters can be seen which burns.
DIAGNOSIS AND TESTING
If you have an allergy, you should tell your doctor about the symptoms you are having, the time when they happen, how often they occur and what seems to trigger them. Then your doctor may conduct out tests to identify the allergen that is causing your symptoms. The type of test you are presented will depend on your symptoms, the condition of your skin and any medicines you are taking along with it.
The common test includes:
- Skin prick test
Test is generally the first test which is done while looking for an allergen. The skin is pricked with a small amount of the suspected allergen to see if there is a reaction. If there is, then the skin around the prick will very quickly become itchy, red and swollen.
This testing is considered very safe and can be used on any age group, including babies as the test introduces such a tiny amount of allergen into the skin. It is not be suitable if you have severe eczema or if you are taking any antihistamines.
- Blood test
This test is very apt way for measuring the of IgE antibodies in your blood that is produced by your immune system in response to a suspected allergen. The results are given on a scale from zero to six.
Zero = negative result
Six = extremely high sensitivity.
Blood tests are predominantly useful when you are at risk of an extreme reaction or when a rare allergen is suspected.
- Patch test
The test is utilized to find an allergen causing eczema. A very small amount of the suspected allergen is added to a special metal discs, which are then taped to your skin for 48 hours and monitored for a reaction. This test is mostly carried out at a dermatology (skin) department in a hospital.
TREATMENT AND CONTROL
|Antihistamines||Oral||Cetirizine,Desloratadine, Fexofenadine||reduce inflammation and swelling|
|Nasal||Olopatadine(drops),Ofloxacin, Azelastine (spray)|
|Eye drop||Ketotifen, Pheniramine, Emedastine|
|Decongestants||Oral||Pseudoephedrine||are used for quick ,brief relief of congestion|
|Eye drop||Tetrahydrozoline ,Naphazoline|
Mast cell stabilizer(MCS)
Eye drops: Lodoxamide, Nedocromil, Pemirolast
|target leukotriene receptors to reduce allergic symptoms|
|Emergency||Epinephrine shots||used to treat anaphylaxis|
The above given table describes a range of drugs and the classes they belong to along with the different forms available like pills, liquids, inhalers, nasal and eye drops, skin creams and shots (injections).
HOW TO PREVENT ALLERGIES?
- Limit your exposure to allergens
- Enforce restricted contact to animal /pet
- Wear personal protective equipment like masks to avoid triggers
- Use of good personal hygiene:
- Always wash hands after coming in contact with animals and before leaving the laboratory or in any other way when you come closer to animals
- Do not eat, drink, smoke, handle contact lenses, use cosmetics in work areas and wash your hands before engaging in any of these activities
- Wash your bedding in hot water (130 to 140 degrees) once a week to kill dust mites. Freezing bedding overnight will also destroy the mites
- Follow proper clean housekeeping measures
- Pay attention to pollen counts. Try to stay indoors when the pollen count is highest, generally in the early morning. Levels are lower in late afternoons and after a soaking shower of rain
- Keep away from the thing that causes stress
- In houses maintain humidity above 50 degrees
- Limit exposure to smoke during pregnancy, after delivery and breast feeding