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Allergy
An allergy is an immune response to a substance that is usually harmless. The immune system treats the substance, called an allergen, as a threat and overreacts to it. Common allergens include pollen, animal dander, dust mites, mold, and certain foods.
Symptoms of allergy can include:
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itching
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congestion
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runny nose
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watery eyes
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Food allergy symptoms can be more serious, and include:
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nausea
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diarrhea
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vomiting
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respiratory symptoms including anaphylaxis.
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The first step in managing allergies is having a diagnosis. Visit our Types of Tests page to read about allergy testing methods. Your allergist may conduct supplemental testing when appropriate (oral challenge).
Select from the list of allergies to learn more, including some methods of treatment.
Food Allergy
Food allergies occur when the body’s immune system has a negative reaction to consuming or being exposed to certain types of food or produce.
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Diagnosis
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In addition to the usual Allergy Testing, food allergy testing may include an Oral Food Challenge (OFC), also known as a feeding test. The test is performed to identify/confirm an allergy to a suspected food allergen under medical supervision.
The oral food challenge test may start by having the patient touch the food item to the lips, or tongue.
Next, the doctor will have the patient eat small amounts of the food item; small portions are unlikely to trigger an allergic reaction. Gradually, the portions will be increased if a reaction occurs.
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Treatment
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After diagnosis, the allergist will discuss food avoidance techniques, and can prescribe medication; most often antihistamines.
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Learning to live with a new food allergy may mean your lifestyle will require more planning, an increase in awareness of what you are eating, and what foods or produce you come into contact with. Patients should educate themselves about their allergy while working with our allergist to find a medication that best fits their needs.
Venom
No one likes to be stung by an insect. While it’s an uncomfortable experience for everyone, the resulting effects may be more pronounced in certain individuals. This is due to an allergen found in insect venom.
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The top 5 insects known to cause an allergic reaction are:
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Honeybees/ bumblebees
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Hornets
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Wasps
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Yellow jackets
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Fire ants
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Symptoms
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Note: Some may not experience an allergic reaction from their first insect sting. Symptoms may not appear until the second or third exposure to the insect’s venom.
Common
itching
hives
local swelling
Anaphylaxis
hives
swelling in the throat or tongue
difficulty breathing
dizziness
nausea
diarrhea
Treatment
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The allergist can prescribe certain medications, an EpiPen or recommend a course of Venom Immunotherapy.
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Venom Allergy Immunotherapy, or allergy shots, are proven to be very effective in treating insect venom allergies. Allergen immunotherapy treatment can help prevent a serious reaction if/when a patient is stung by an insect.
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Avoidance
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Note: stinging insects are most active in late spring, summer, and early fall, and that insect repellents do not work against them.
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Stay clear of stinging insects’ nests or perceived territory.
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If you encounter flying insects, remain calm and quiet, and move slowly. Do not “swat” them.
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Many stinging insects are searching for nectar; a sweet flavoured liquid found in, among other things, colourful wildflowers. Avoid brightly colored clothing and perfume when outdoors.
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Be careful when cooking, eating or drinking sweet drinks, like soda or juice, outdoors – the smell of food attracts insects. Keep food covered until eaten.
Animal
Allergies to pets and other animals are common. Individuals who have been diagnosed with Asthma or other allergies may be more susceptible.
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A common misconception is that reactions are caused by an animal’s fur. Fur, however, is not an allergen. Your reaction is more likely being caused by the proteins in an animal’s urine, dander, or saliva.
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Treatment
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Avoidance is the most effective way to limit/eliminate your allergy symptoms. Avoid the animal to avoid the symptoms. If the animal is a beloved family pet, full avoidance (finding a new home) is not always an option. In such cases, it may be helpful to reduce direct contact with the pet.
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Alternatively, the most common method for dealing with animal allergy symptoms is though medication. Our allergists will recommend a prescription that best fits your symptoms.
Allergen Immunotherapy is also an option for treating certain animal allergies, but has not been proven to be as effective as the immunotherapy treatment given for environmental allergies.
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Penicillin
Penicillin is widely known and used as an antibiotic, and is the most common cause of drug allergies. Allergic responses to penicillin are not typically categorized as dangerous anaphylactic reactions. Their symptoms include rashes, itchy eyes, hives, or swelling in the face, tongue or lips.
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Penicillin Antibiotics Include:
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Amoxicillin
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Ampicillin
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Dicloxacillin
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Oxacillin
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Penicillin G
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Penicillin V
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Piperacillin
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Ticarcillin
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Treatment
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Mild allergic reactions to penicillin can be controlled using antihistamines, which can be bought without a prescription. If over-the-counter antihistamines do not help, your allergist or family doctor can prescribe different medications, such as an antibiotic.
Environmental
Pollen-producing plants - trees, grass, and ragweed - are the culprit behind most seasonal allergies. Patients typically react to the pollen, and not the plant, therefore symptoms occur during the plant's pollination phase.
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Pollen counts tend to surge on warm and windy days.
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Pollination times of the 3 most common allergy-causing plants:
Mold Spores
Dust Mite
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Dust mites are a common – yet relatively unknown allergen; Dust mites are tiny insects, closely related to ticks, which live in household dust, and are a common household allergen.
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Dust mites thrive in the bedroom environment more than anywhere else in a household. Although dust mites are everywhere, a few simple environmental measures can dramatically improve your allergy and asthma symptoms, as well as decrease the amount of medication you may currently require.
Dust mite avoidance is the safest most effective ways to avoid symptoms.
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Latex
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Natural rubber latex is a byproduct of sap from the rubber tree; as such, it is technically categorized as an environmental allergy. Symptoms present themselves if patients are sensitive to the proteins found in the natural rubber latex.
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Rubber gloves are the main source of allergic reactions, although latex is also used in other products such as condoms and some medical devices.
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Treatment
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Once the allergen(s) has been identified, the allergist may prescribe medication (usually an antihistamine) or a course of Allergen Immunotherapy. Immunotherapy has been proven to be very effective in treating several environmental allergies.
Oral Allergy Syndrome
Oral Allergy Syndrome(OAS) is an allergy to certain raw fruits, vegetables, seeds, spices and nuts which causes an allergic reaction in the mouth and throat. These allergic reactions happen mostly in people with hay fever, especially spring hay fever, due to birch pollen and ragweed pollen.
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Oral Allergy Syndrome is classified by the response of allergic reactions in the mouth, and regions close in proximity. There may be swelling of the lips, tongue and throat, along with watery, itchy eyes, a runny nose and sneezing.
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Handling the raw fruit or vegetable or touching the juice to the lips may cause a rash, itching or swelling where the juice touches the skin.
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Other symptoms include sneezing, runny nose and watery eyes. Sometimes, more severe symptoms can occur, such as vomiting, cramps, diarrhea and, on rare occasions, life threatening reactions with swelling of the throat, wheezing, trouble breathing and anaphylaxis.
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Treatment & Tips
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Oral Allergy Syndrome is caused by raw fruits or vegetables. Once they are cooked or processed, they can usually be eaten.
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You do not need to avoid all raw fruits or vegetables. Avoid only those particular fruits and/or vegetables which have caused allergic reactions.
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If you do have Oral Allergy Syndrome to certain foods, you may still be at risk of developing allergies to other foods.
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If an allergic reaction occurs with any food, stop eating it immediately. Mild allergic reactions may be treated with antihistamines. Severe reactions may happen if you continue consuming that food item.
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If you have had severe symptoms including trouble breathing when eating the food item in question, you may need to carry injectable medication with you to treat these reactions (e.g., EpiPen®).
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For mild Oral Allergy Syndrome, try peeling the fruit, or eating unripe or partially ripe fruits, or picking them directly from the tree so that they are quite fresh. If you react, do not keep eating the food.
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Microwaving briefly to a temperature of 80-90 degrees Celcius may allow you to eat the food if it is a mild allergy.
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Nuts which cause Oral Allergy Syndrome should be avoided altogether, fresh or cooked. They carry with them a substantially higher risk of inducing severe reactions.
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Allergy shots for hay fever may sometimes help with associated food allergies.
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