What is an allergy?

An allergy is an overreaction of your body’s immune system to something that is harmless to most people. Normally, your immune system acts in defense against a foreign substance like a virus or bacteria. It will try to destroy anything it feels could harm the body. When it falsely identifies a harmless substance as an invader, it tries to protect your body. The resulting symptoms are an allergic reaction.

Items that people are allergic to are referred to as allergens. In order for your immune system to develop sensitivity to an item, you must be exposed to that item at least once prior to developing the allergy. The body goes through a sensitization period, which is why it may take a few days, or even a few years, for someone to develop allergies to a particular thing.

Who is at risk of developing allergies?

It is estimated that about 50 million North Americans are affected by allergies. Though they are commonly diagnosed in children, allergies can develop at any age at any time.

The strongest distinguishing factor for being at risk of having or developing allergies is heredity. If neither parent is allergic, then the chance of the child developing allergies is about 15%; if one parent has allergies, the chance increases to 30%; and if both parents have allergies, the chance increases again to 60%. However, even though you may have inherited the risk to develop allergies, you may not be allergic to the same things as your parents or experience any allergic symptoms at all. Another factor in developing allergies is environment. People can develop allergies after prolonged and repetitive exposure to something.

What are the symptoms of allergies?

There are different types of allergic conditions. Symptoms vary depending on the individual, the specific allergen and how the allergen enters the system.

Respiratory allergies – The most common allergies are respiratory and can be either seasonal or perennial. Both occur as a result of something in the air we breathe. Symptoms of respiratory allergies include:

  • Runny or stuffy nose
  • Sneezing
  • Itchy, watery eyes
  • Itchy ears and throat
  • Red, swollen eyes

Respiratory allergies can also trigger asthma attacks. These attacks can be quite severe and often include:

  • Coughing
  • Tightness or heavinesss in chest
  • Shortness of breath
  • Wheezing

‘Seasonal allergies, also known as hay fever, occur at the same time each year – often during the spring, summer, or fall seasons when plants are releasing pollens and seeds into the air. Depending on what you are sensitive to, you may only suffer from symptoms for a couple weeks, or you may suffer for several months.

Perennial allergies are caused by allergens that are usually found indoors such as mould, dust mites, and animal dander (skin flakes). These allergens are present all year round and cause symptoms whenever a person comes in contact with them.

Allergies from ingested substances – When food or medications are ingested, the allergens sometimes gain access to the bloodstream and can produce symptoms in areas both inside and outside the gastro-intestinal tract. Reactions to ingested allergens can include:

  • Diarrhea
  • Stomach cramps
  • Tongue and throat swelling
  • Nausea
  • Difficulty breathing
  • Skin rashes or hives
  • Low blood pressure or anaphylactic shock

The most common ingested allergens are cows’ milk and other dairy products, shellfish, eggs, peanuts and other nuts, soy, wheat, MSG, sulphites (used in preservation), tartrazine (a food dye), and some antibiotics. Severe reactions to ingested allergens such as peanuts can be fatal.

Allergic contact dermatitis – This is an allergic reaction caused when your skin has contact with a substance your body is sensitive to. In most cases, the skin acts as a barrier and the reaction remains outside your body, but occasionally some allergens such as latex can be absorbed by the skin and case reactions in other parts of the body. Skin reactions to allergens can include:

  • Itching, redness, or dryness of skin areas
  • Rash on face and around the eyes
  • Rash in elbow creases and behind the knees
  • Hives

Substances such as latex, plants, dyes, chemicals, metals, and cosmetics are known to cause allergic reactions upon contact with sensitive people.

Allergies from injected substances – When an allergen is injected directly into the blood stream, it can cause severe and even fatal reactions in sensitive people. (eg: insect stings and injected medications). Reactions to injected allergens can include:

  • Red and itchy skin
  • Tongue and throat swelling
  • Nausea
  • Diarrhea
  • Stomach cramps
  • Difficulty breathing
  • Low blood pressure or anaphylactic shock

Severe reactions can very quickly affect multiple organs all at once. They are not predictable – you can have a severe reaction one time and a mild one the next. If you suspect that an allergy could potentially cause anaphylactic shock, visit an allergy specialist for confirmation.

How can I manage my allergies?

The best way to reduce allergy symptoms is to identify your personal allergens and avoid them as much as possible.

Seasonal allergies – These allergens can be avoided by trying to stay indoors during periods of high pollen in the air and using air conditioners in your house and car.

Perennial allergies – Exposure to mould and dust mites can be reduced by making some changes to your environment. Controlling the air quality and reducing humidity will have a great effect on the moulds and dust mites in your home. Frequent cleaning, increased air circulation and reduced clutter also aid in this area. If allergies are severe, removing carpets, enclosing mattresses in impermeable casings, and washing bed linens on a weekly basis can substantially reduce your allergy symptoms. If you are allergic to animal dander and you have a pet that causes a reaction, consider finding the pet a new home or keeping it outside. In any case, the pet should not be allowed in your bedroom.

Food/Drug allergies – It is important to be aware of what you are ingesting. Get into the habit of reading labels on packages and asking questions in restaurants. Make sure your health care professional is aware of your allergies and wear a medic alert bracelet.

Severe allergies – Wear a medic alert bracelet and make sure everyone you know is aware of your allergy and knows what to do if a reaction should occur. Severe reactions are usually treated with an injection of epinephrine (adrenalin), antihistamines, and/or steroids. An EpiPen® Is a device that allows you to give yourself an injection quickly if necessary. If you should have to use one, you should also go to the hospital for observation.

Can allergies be treated with medication?

There are several medications available to treat allergies. Many antihistamines, decongestants and nasal sprays can be purchased without a prescription. They are very effective in reducing allergy symptoms but can react with other medication or can affect particular health conditions such as high blood pressure or pregnancy. Consult your Calgary Drugmart pharmacist before purchasing such allergy medications.