What are Allergies?

Allergies are a common chronic condition, in which the immune system reacts to typically harmless substances in the environment. These substances are known as allergens. Common allergens include pollen, dust, food, insect stings, animal dander, mold, medications, and latex. Often allergic reactions produce symptoms in the throat, nose, lungs, sinuses, ears, lining of the stomach or on the skin.

You should seek testing by an allergist if you experience any of the following symptoms

  • Itchy eyes, nose or throat
  • Runny nose, watery eyes, nasal or chest congestion, coughing, wheezing
  • Hives, itchiness, atopic dermatitis
  • Severe reactions to insect stings other than swelling
  • Consistent abdominal cramping, hives, swollen lips
  • Anaphylaxis

Types of Allergies

Seasonal Allergies

Also known as hay fever or seasonal allergies, this allergic response causes itchy, watery eyes, sneezing, and a runny or stuffy nose. Like other allergies, rhinitis develops when one’s immune system becomes overly sensitized to something in the environment, triggering a reaction. Symptoms of seasonal rhinitis often surface in the spring, summer, and early fall. Hay fever triggers include outdoor allergens (pollens from grass, trees, weeds), and indoor allergens (pet hair, dander, dust mites, mold). If you experience these symptoms, it would be helpful to see an allergist for more effective treatment including antihistamines and allergy shots (i.e. immunotherapy).

Food Allergies

This type of allergy is most common in children, though it can surface at any age. A food allergy occurs when the body overreacts to certain foods, identifying them as dangerous, which triggers a protective response from the immune system. Symptoms of food allergies range from mild to severe. The most common types of foods that account for 90% of food allergies are: peanuts, tree nuts, eggs, milk, fish, shellfish, wheat, and soy. One can become allergic to certain foods after having eaten them for several years without problem.

Pet Allergies

People with pet allergies experience watery eyes, sneezing, wheezing, coughing, or a skin rash during or after interactions with dogs or cats. Pet allergies can cause allergy symptoms even for 6 months after the pet has been removed.

Insect Allergies

Stings from honeybees, hornets, wasps, yellow jackets, and fire ants are known to often cause allergic reactions when the venom is injected into one’s skin. While there is some reaction usually triggered after an insect sting, one should be wary if they experience any of the following allergic reaction symptoms: pain, redness, swelling in areas beyond the sting site, flushing, hives, itching, anaphylaxis. Allergic reactions to stings can even surface later in life after many years of normal reactions, so it is important to be cognizant of more severe symptoms that signal an allergic reaction.

Dust Allergies

People with dust allergies often suffer inside the house, with symptoms worsening during or after vacuuming, sweeping, or dusting. Common house allergens include dust mites, cockroaches, mold, pollen, and pet hair. Dust allergies make it difficult to breathe, causing symptoms such as wheezing, itching, sneezing, runny or stuffy nose, irritable eyes, coughing, tightness in the chest, and shortness of breath.

Drug Allergies

People with drug allergies experience symptoms after taking certain drug medications, including itching, wheezing or other breathing problems, hives, swelling, or anaphylaxis. Such symptoms may surface regardless if the medicine is in liquid, pill, or injectable form. Common triggers of drug allergies include antibiotics containing sulfonamides, penicillin, anticonvulsants, chemotherapy drugs, aspirin, ibuprofen, and other nonsteroidal anti-inflammatory drugs.

Skin Allergies

The causes of common skin conditions, such as bumps, itchiness, and redness, can be difficult to determine. Allergic reactions to medications, food, or plants can sometimes cause these symptoms. Eczema and hives are the most common skin rash allergies.

Eye Allergies

Also known as allergic conjunctivitis, eye allergies are a condition in which one experiences itching, redness, burning, and clear watery discharge in their eyes. These symptoms often complement a nasal allergy, so it is important for people to treat both their nasal and eye allergies to prevent further discomfort.

Allergy Testing

Since allergens affect individuals differently, Dr. Celina P. John will determine on a case-by-case basis what test is best for you. Common tests include:

Skin Tests

Conducted in the allergist’s office, skin tests are most common kind of allergy test. Dr. Celina P. John will inject you with a small amount of allergens through a small prick on the surface of the skin. If you have allergies, your skin will slightly swell or produce small hives at the point of the prick within fifteen minutes. One advantage of skin tests over blood tests is that they can more accurately pinpoint what you’re exactly allergic to.

Blood Tests

These tests are done when skin tests may be unsafe or unable to predict the allergy. For example, when the patient is taking certain medications or has a skin condition that could interfere with the skin test. Since this method involves drawing blood, the results are not available as quickly as skin test results.

Challenge Tests

These tests are done mainly for potential food or medication allergies, in which the patient inhales or ingests a small amount of the allergen. The subsequent reaction to the allergen is then monitored by the allergist.

Allergy Treatments

Treatments for allergies include: (1) avoiding the known allergens, (2) taking medication, and (3) immunotherapy.


Allergists can prescribe antihistamines to relieve allergy symptoms. Antihistamines block histamine, a chemical that can cause allergic reactions. There are several forms of antihistamines including pills, liquids, nasal sprays, and eyedrops.


A treatment in which the patient is gradually vaccinated with incrementally larger doses of the problematic allergen. This desensitization process can either reduce the severity of the allergy or eliminate it completely.