Allergy also known as allergic diseases are a number of conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include red eyes, an itchy rash, sneezing, a runny nose, shortness of breath, or swelling. Food intolerances and food poisoning are separate conditions.
Allergies can strike anytime, and anywhere. They’re one of the most common ailments, affecting millions of people each year. There are many causes of allergies, including organic and inorganic matter. Allergies develop as a result of a hypersensitive reaction by your immune system to a foreign substance, causing a range of symptoms to appear. While most allergic reactions are not severe, some people may develop life-threatening complications. Contact your doctor if you suspect being allergic to something.
Causes of Allergy
Latex allergies are among the most common types of allergies in the Western world. This kind of allergy usually develops as a reaction to previous exposures to latex. People who suffer from latex allergy are likely to experience itching, swelling, and hives in the area exposed to the material. In more severe cases, it can cause wheezing, difficulty breathing, as well as a headache. Depending on the sensitivity level, symptoms may develop a few minutes after exposure, and up to an hour afterward. Luckily, latex-free products can easily be found in most supermarkets.
More than 20 million people in the US suffer from allergies due to dust mites, making this by far one of the most common causes of allergy. Dust mites are tiny, microscopic creatures that consume dead skin cells, both human and animal. Dust mites are notorious for their ability to persist even in the harshest of climates. The higher a number of dust mites, the more severe symptoms will appear. Another conditioning factor is the degree of sensitivity. Symptoms can range from mild, including coughing and itching, to more serious symptoms.
Another frequent cause of allergy is nickel. Nickel is a metal that is most often found in different jewelry, such as earrings, bracelets, and rings. The skin around the ear can be especially sensitive to nickel, causing symptoms such as itchiness and irritation. In some cases, earrings containing nickel may lead to infections of the skin. To ensure that your earrings are nickel-free, look for a certifying engraving that can be found on the metallic earring locks. You can also consider wearing wooden jewelry, which is 100% free of nickel. To test for symptoms, rub your earring on the skin of ear and look for red patches of skin.
As terrifying as it may sound, cockroaches are one of the most probable causes of allergic symptoms. Cockroaches can trigger symptoms in many people due to a unique protein found in their excrement and saliva. When it enters contact with humans, it can cause symptoms affecting the skin, lungs, and eyes. In some cases, cockroaches can even trigger an asthma attack. To reduce the risk of a cockroach infestation, make sure there is no food lying around the house, and remove any excess moisture from walls and the floor. If you still report symptoms, contact an exterminator.
Many people enjoy wearing alluring fragrances to work or just for a night of partying. Perfumes and colognes have been an important part of cosmetic history for many centuries already. These aromatic substances are made with a variety of ingredients, some natural and some artificial. Most people can wear them just fine, but a few may experience an allergic reaction. You may experience rashes, swelling, and itchiness on the skin if you are allergic to fragrances. Soap, shampoo, and dental products may provoke similar symptoms. You can always shop for products that are free from irritating substances.
Many people suffer from food allergies: in fact, you may be one of more than 15 million Americans that report some food or drink allergy. Some of the most common forms of food allergy include nuts, milk, soy, fish, and onions. You are considered to have a food allergy if your body’s immune system reacts aggressively to the presence of certain foods. Depending on the person, symptoms can range from mild to severe. Some of the most frequent symptoms include a cough, diarrhea, vomiting and stomach ache. Severe symptoms can be life-threatening, so seek medical attention if you experience difficulty breathing, dizziness, or severe pain.
If you live in a damp, wet environment that experiences frequent rainfall and humidity, you may be at risk of developing household mold. Mold can grow nearly anywhere as long as the bacteria that cause it can thrive. Mold is classified as a fungus, and it can reproduce and spread. If mold particles enter the nasal passage, they can provoke allergic symptoms to develop, including irritation of the eyes, cough, as well as asthma attacks. To reduce the presence of mold, ensure that surfaces are kept dry and free from moisture.
In most cases, symptoms related to allergies are caused by organic matter, such as pollen or animal fur. While these are often the most common trigger of allergies, they aren’t the only ones. Many human-made and artificial products can also cause an allergic reaction to take place, including many cosmetics. That’s why women – who wear the most amount of makeup – are more likely to experience these symptoms. One of the most common allergens is quaternium 15, which is a type of preservative abundantly found in different cosmetic products. Shampoo, nail polish, and sunscreen are just a few of the products containing it.
Pollen allergy is one of the most common forms of allergy in the USA. It is caused by an allergic reaction that takes place inside the body when it becomes in contact with pollen. Pollen is a powder that is produced by different organisms, including trees, flowers, as well as weeds. Many people suffer from pollen allergies, which is why spring is also known as the allergy season. If pollen finds its way into your nasal passage, throat, or lungs, it may trigger an allergic reaction. Some of the main symptoms include coughing, swelling, itching, and even pain.
Symptoms of Allergy
Symptoms of a food allergy may include
Tingling in the mouth
Swelling of the lips, tongue, face, or throat
Anaphylaxis (a severe, life-threatening allergic reaction)
An insect sting allergy may cause
A large area of swelling at the site of the sting
Wheezing, cough, chest tightness, or shortness of breath
Itching or hives all over your body
A reaction to medications may lead to
Hives (small red spots especially on the chest, back, or abdomen) or other rashes
Airborne allergies can cause allergic rhinitis (hay fever), which is characterized by
Finding out exactly what’s causing your allergies is an important step to ensuring you receive effective allergy treatment. If you think you have allergies, your doctor will probably recommend that you see an allergy specialist. Your allergist may perform a physical exam, look at your medical history, and perform the following tests:
Skin test – In this test, concentrated drops of various allergens are pricked or scratched on the surface of the skin. If you’re allergic to any of these allergens, you’ll develop a red bump (hive), redness, and swelling at the test spot. Doctors sometimes recommend a second type of test, in which a small amount of the allergen is injected into the skin of the arm. Certain medicines may interfere with the interpretation of allergy skin tests, so be sure to tell your healthcare provider about any prescription or over-the-counter (OTC) drugs you’re taking.
Blood test– A test known as the radioallergosorbent test (RAST) measures the amount of allergy-causing antibodies in your bloodstream (known as IgE antibodies).T he RAST test can help doctors measure your immune system’s response to a particular allergen.
IgE Test – The test measures the concentration of specific IgE antibodies in the blood. Quantitative IgE test results increase the possibility of ranking how different substances may affect symptoms. A rule of thumb is that the higher the IgE antibody value, the greater the likelihood of symptoms. Allergens found at low levels that today do not result in symptoms can nevertheless help predict future symptom development. The quantitative allergy blood result can help determine what a patient is allergic to, help predict and follow the disease development, estimate the risk of a severe reaction, and explain cross-reactivity.
A low total IgE level is not adequate to rule out sensitization to commonly inhaled allergens. Statistical methods, such as ROC curves, predictive value calculations, and likelihood ratios have been used to examine the relationship of various testing methods to each other. These methods have shown that patients with a high total IgE have a high probability of allergic sensitization, but further investigation with allergy tests for specific IgE antibodies for a carefully chosen of allergens is often warranted.
Laboratory methods to measure specific IgE antibodies for allergy testing include enzyme-linked immunosorbent assay (ELISA, or EIA), radioallergosorbent test (RAST) and fluorescent enzyme immunoassay (FEIA).
Patch test – Patch testing is a method used to determine if a specific substance causes allergic inflammation of the skin. It tests for delayed reactions. It is used to help ascertain the cause of skin contact allergy, or contact dermatitis. Adhesive patches, usually treated with a number of common allergic chemicals or skin sensitizers, are applied to the back. The skin is then examined for possible local reactions at least twice, usually at 48 hours after application of the patch, and again two or three days later.
Allergic conditions: Statistics and epidemiology
35.9 million (about 11% of the population)
3.3 million (about 5.5% of the population)
10 million have allergic asthma (about 3% of the population). The prevalence of asthma increased 75% from 1980 to 1994. Asthma prevalence is 39% higher in African Americans than in Europeans.
5.7 million (about 9.4%). In six- and seven-year-olds asthma increased from 18.4% to 20.9% over five years, during the same time the rate decreased from 31% to 24.7% in 13- to 14-year-olds.
About 9% of the population. Between 1960 and 1990 prevalence has increased from 3% to 10% in children.
5.8 million (about 1% severe).
At least 40 deaths per year due to insect venom. About 400 deaths due to penicillin anaphylaxis. About 220 cases of anaphylaxis and 3 deaths per year are due to latex allergy. An estimated 150 people die annually from anaphylaxis due to food allergy.
Between 1999 and 2006, 48 deaths occurred in people ranging from five months to 85 years old.
Around 15% of adults have mild, localized allergic reactions. Systemic reactions occur in 3% of adults and less than 1% of children.
Anaphylactic reactions to penicillin cause 400 deaths per year.
About 6% of US children under age 3 and 3.5–4% of the overall US population. Peanut and/or tree nut (e.g. walnut) allergy affects about three million Americans, or 1.1% of the population.
5–7% of infants and 1–2% of adults. A 117.3% increase in peanut allergies was observed from 2001 to 2005, an estimated 25,700 people in England are affected.
Multiple allergies (Asthma, eczema and allergic rhinitis together)
2.3 million (about 3.7%), prevalence has increased by 48.9% between 2001 and 2005.
Mechanisms and Clinical Manifestations of IgE-Associated Food allergy
Organ systemClinical manifestationsImmunopathologyFeaturesAge and natural courseSkin
Urticaria, angio courses
Oral allergy syndrome (local itching and tingling and/or edema of lips, tongue, palate, and pharynx)
IgE-mediated mast cell/basophil degranulation
Acute onset after food ingestion (minutes-hours)
In infants and adults, may resolve with age
Appears mainly in adults with established pollen allergies, long-lived, boosted by pollen contact
After direct skin contact
In infants and adults
Protein contact dermatitis
T cell-mediated (with or without the involvement of IgE)
Delayed type reaction > 24 hours after food ingestion
T cell-mediated (with or without involvement of IgE)?
Delayed type reaction > 24 hours after food ingestion
Treatment of Allergy
There are no cures for allergies, but effective treatment can reduce symptoms and improve your quality of life.
If your allergies are severe enough to significantly interfere with your quality of life, it’s a good idea to see a doctor in order to identify what you are allergic to and to gain access to the full range of prescription options.
If your allergies are less severe or merely annoying, you may be able to find an effective over-the-counter (OTC) treatment. A pharmacist may be able to help you choose the best option based on your symptoms.
Certain medications can help reduce your immune system’s reaction to allergens, which eases symptoms. Allergy drugs come in both OTC and prescription forms. They can be taken as liquids, pills, nasal sprays, or eye drops.
These medicines relieve congestion by shrinking swollen nasal tissues and blood vessels, and are often prescribed along with antihistamines.
Examples of decongestants include:
Neo-Synephrine or Afrin (oxymetazoline)
Some forms of Visine eye drops
(fexofenadine and pseudoephedrine), Zyrtec-D (cetirizine and pseudoephedrine), and Claritin-D (loratadine and pseudoephedrine) contain both a decongestant and an antihistamine.
Mast cell stabilizers
These medications block the release of immune system chemicals that play a role in allergic reactions.
Examples of mast cell stabilizers include:
These drugs can help reduce inflammation and swelling.
Common steroids for allergies include:
Flonase or Veramyst (fluticasone)
Sometimes therapies typically used for asthma — such as leukotriene receptor antagonists (LTRAs), bronchodilators, and certain steroids — are prescribed to help treat allergy symptoms.
This medicine is used to treat anaphylaxis (a severe, life-threatening allergic reaction) until emergency treatment is administered.
Epinephrine is administered as a shot.
Allergy shots — also known as allergen immunotherapy — can be given to reduce sensitivity to certain allergens and improve symptoms.
This therapy involves injecting small amounts of allergen extracts into your body to stimulate your immune system, without causing an allergic reaction. Your doctor will increase the allergen dose over time.
The shots work like a vaccine, as your body develops immunity and tolerance to particular allergens after being exposed to them.
They’re typically given over the course of three to five years.
Both adults and children can receive allergy shots, but they’re usually not recommended for children under age 5.
Allergy drops for the mouth — known as sublingual immunotherapy — are a newer way to acclimate the body to allergens without injections.
In this therapy, a small dose of an allergen is delivered under the tongue to boost tolerance and immunity. The therapy is typically taken at home.
This treatment is gaining popularity in the United States, but it’s still not considered an established therapy by the Food and Drug Administration (FDA).
It is useful for environmental allergies, allergies to insect bites, and asthma. Its benefit for food allergies is unclear and thus not recommended. Immunotherapy involves exposing people to larger and larger amounts of allergen in an effort to change the immune system’s response.
Meta-analyses have found that injections of allergens under the skin is effective in the treatment in allergic rhinitis in childrenand in asthma. The benefits may last for years after treatment is stopped. It is generally safe and effective for allergic rhinitis and conjunctivitis, allergic forms of asthma, and stinging insects.
The evidence also supports the use of sublingual immunotherapy for rhinitis and asthma but it is less strong. For seasonal allergies the benefit is small. In this form, the allergen is given under the tongue and people often prefer it to injections. Immunotherapy is not recommended as a stand-alone treatment for asthma.
Immunotherapy for food allergy
Type of drug
Blocks IL-33-induced signalling, which normally favours TH2 cell-mediated allergic responses
Presentation of peanut protein without inflammation induces tolerance
Phase I and preclinical
CoFAR, Consortium for Food Allergy Research; EoE, eosinophilic oesophagitis; EPIT, epicutaneous immunotherapy; IL, interleukin; LEAP, Learning Early About Peanut Allergy; NA, not applicable; OIT, oral immunotherapy; SLIT, sublingual immunotherapy; SPT, skin prick test; TH2, T helper 2; Treg cell, regulatory T cell
One of the most important steps you can take to reduce your symptoms is to avoid allergy triggers.
Allergic reactions can still occur, even if you’re diligent about staying away from known allergens.
Allergy Medicine While Pregnant
Certain allergy medicines are safe to take during pregnancy, while others aren’t.
Talk to your doctor about the risks and benefits of taking these drugs while you’re pregnant.
Your healthcare provider can help you choose the safest treatment option for you and your baby.
Home Remedies for Allergy
You can reduce many allergy symptoms at home by taking the following steps
Performing saline nasal irrigation
With this method, you rinse out your sinuses with a saltwater solution to reduce congestion.
You can use a or a special squeeze bottle. Be sure to follow all usage and cleaning instructions provided by the manufacturer.
Washing bedding frequently
You can greatly reduce your exposure to dust mites and pet dander by washing bedding and other items often. Be sure to use hot water.
Consuming local honey
There’s little scientific evidence to back up this remedy, but some people report fewer allergy symptoms when they eat honey produced by bees in their region.
Using a high-efficiency particulate air (HEPA) filter
These filters trap allergens and other airborne irritants, which may reduce your symptoms.
Replacing carpeting with hard flooring
This makes it easier to keep surfaces clean and free of possible allergens.
Taking herbal or other dietary supplements
Certain herbs, like butterbur extract, may reduce allergy symptoms in some people, but there is little scientific evidence to support these claims.
Talk to your doctor about the risks and benefits of any dietary supplement before taking it.
Home Remedies for Allergy
Spring brings warmer weather and longer days, while the autumn ushers in crisp air and pumpkin-spice lattes. But these seasonal changes aren’t welcomed by everyone. For many of us, they’re eclipsed by the itchy eyes, sneezing, and congestion of hay fever and other allergies. What to do?
Some allergies are severe and require the attention of a doctor or other health care professional. For milder cases, though, home remedies may provide all the relief you need, with relatively little expense or hassle. Even people with bad allergies who need medication may find these at-home tips helpful for easing symptoms.
They may look exotic, but Neti pots are fast becoming a mainstream remedy for allergies and stuffed-up sinuses. The treatment, which involves rinsing your nasal cavity with a saline solution, flushes out allergens (like pollen) and loosens mucus.
Using a Neti pot is simple. First, fill the pot with a mixture of salt and warm water (you can buy premeasured kits or make your own). Then tilt your head to the side and pour the solution in one nostril until it flows out the other, repeating the process on the opposite side. (Important note: Use boiled or distilled water only, as tap water can introduce potentially dangerous organisms into your system.)
Prepackaged saline nasal sprays function much like Neti pots, but some allergy sufferers may find them easier to use. Sprays deliver saline solution a bit more gently and evenly, whereas pots can sometimes be a little “sloppy,” says Robert Graham, MD, an internist and integrative medicine specialist at Lenox Hill Hospital, in New York City.
Saline sprays should provide comparable results. Although Neti pots have been studied more extensively, and in some cases may prove more effective, sprays too have been shown to help with allergy symptoms and other sinus problems.
Eating honey produced by bees in your region can help relieve allergies. The bees transfer pollen from flower blossoms to honey, so if you eat a little honey every day you’ll gradually become inoculated against the irritating effects of pollen.
That’s the widely held theory, anyway. Unfortunately, there’s little to no scientific evidence to back it up. Although a small 2011 study from Finland that compared regular honey and pollen-laced honey did report modestly encouraging results, an earlier study in the United States found that unaltered local honey had no impact on allergy symptoms.
High-efficiency particulate air (HEPA) filters ease symptoms by trapping allergens and other airborne irritants, such as pet dander and dust. Portable air cleaners equipped with HEPA filters can purify the air in bedrooms and other confined spaces, but whole-house systems that incorporate HEPA filters into your home’s heating, ventilation, and air conditioning (HVAC) system are generally more effective.
Air conditioners and dehumidifiers also can help clean air, Dr. Graham says. They remove moisture from the air and floor, which will curb the growth of the mold and mildew that can worsen allergies.
Herbs and supplements
Several herbs and supplements—including spirulina, eyebright, and goldenseal—have been studied for allergy relief. The plant extract butterbur, which is thought to reduce airway inflammation, has produced what are perhaps the strongest results. In a pair of clinical trials led by a Swiss research team, butterbur tablets eased symptoms just as much as the over-the-counter antihistamines fexofenadine and cetirizine, respectively.
For his part, Dr. Graham suggests his patients first try bromelain, an enzyme found in pineapple that is sometimes used to curb inflammation after sinus surgery. “It reduces swelling and improves breathing,” he says. “It’s a safe first step.”
Anyone who has even been stuffed-up knows the impressive ability of a steaming hot shower to soothe sinuses and clear nasal passages, if only temporarily. But showers offer an added benefit for springtime allergy sufferers. A quick rinse after spending time outdoors can help remove allergens from your skin and hair—and prevent them from spreading to clothes, furniture, pillowcases, and other surfaces where they’re likely to dog you.
This is especially true if you’ve been gardening. The American Academy of Allergy, Asthma & Immunology recommends stripping off your shoes and clothes and showering immediately if you’ve been weeding, pruning, or planting.
Don’t feel like getting soaked and toweling off every time your sinuses get clogged? Other methods of inhaling steam—store-bought vaporizers, for instance—can flush out mucus and moisten dry nasal passages nearly as well as a shower.
The easiest method is simply to pour boiling water into a bowl or other container, drape a towel over your head to form a tent, and inhale deeply through your nose for five to 10 minutes. (Just be careful not to get your face too close to the water, as you may scald yourself.) If you find yourself really clogged up, this may be more convenient than taking several showers a day.
The strong, piney aroma of eucalyptus oil can supercharge steam inhalation, helping to open your sinuses and nasal passages further. Some research suggests the essential oil, extracted from the leaves of the eucalyptus tree, has anti-inflammatory and antibacterial properties, but if nothing else the vapor provides a bracing, menthol-like sensation that can make breathing seem easier.
Try adding a few drops of oil to a bowl of steaming water, or to the floor of the shower before you step in. Just don’t swallow the oil or apply it directly to your skin; it’s toxic in concentrated amounts.
Many people swear by the sinus-clearing effects of spicy foods like chili peppers, wasabi, Dijon mustard, fresh garlic, and horseradish. Sure enough, an active ingredient in garlic (allyl thiosulfinate) and a similar ingredient in wasabi (isothiocyanates) do appear to have a temporary decongestant effect.
Foods with a kick can definitely start your eyes watering and open your nasal passages, but it’s unclear whether they provide anything more than fleeting relief.
Holding your face over a hot cup of tea may open your nasal passages, but the steam isn’t the only thing that’s beneficial. The menthol in peppermint tea, for instance, seems to work as a decongestant and expectorant, meaning it can break up mucus and help clear it out of your nose and throat.
Similarly, green tea contains a compound (methylated epigallocatechin gallate) that has been shown in lab teststo have antioxidant properties that inhibit allergic reactions. These results may not necessarily translate into noticeable symptom relief for spring allergy sufferers, however.
If you do have spring allergies, you’ll probably want to stay away from chamomile, as it can cause reactions in people allergic to ragweed.
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