Do I Have Allergies?

What are Allergies?

Allergies are hypersensitive immune responses to substances that enter or come into contact with the body. These substances, known as allergens, can be inhaled, ingested, or touch the skin or mucous membranes. While these substances are generally harmless for most people, in allergic individuals, the immune system identifies them as threats and overreacts in allergic individuals, leading to allergic symptoms. Allergists like Dr George Samra, have skills in unmasking specific allergies, suffered by allergic individuals. Unmasking and identifying specific allergies and sensitivities is the first and a most important step in the process leading to successful management.

Risk Factors for Allergies

While anyone can develop an allergy at any point in their lives, some people are more at risk than others. Factors that increase the risk for allergies include:

Family history: If allergies and asthma run in the family, you're more likely to develop them.
Age: Allergies can develop at any age but are most common in children. Some allergies (like food allergies in children) might be outgrown, while others persist into adulthood.
Other allergies or asthma: If you have one type of allergy, you might be at an increased risk of developing another.
Childhood exposure: Early exposure to certain allergens (like dust mites or pollen), infections, and certain dietary patterns may influence the development of allergies.
Having atopic dermatitis (eczema): Those with this skin condition might be more prone to developing food allergies, hay fever, or asthma.

Causes of Allergies

Allergies are caused when the immune system overreacts to an allergen. Here are some common allergens and triggers:

Airborne allergens: This includes pollen, mould spores, pet dander, dust mites, and particles released by insects (like cockroach waste).
Food allergens: Common ones include peanuts, tree nuts, milk, eggs, wheat, soy, fish, and shellfish.
Insect stings: From bees, wasps, hornets, yellow jackets, and fire ants.
Medications: Penicillin and some other drugs can cause allergic reactions.
Latex: Found in some types of gloves and condoms.
Contact allergens: Substances that cause skin reactions, like certain metals (nickel), fragrances, and ingredients in cosmetics and cleaning products.

Symptoms of Allergies

Allergic reactions can range from mild to severe. Common symptoms include:

Respiratory Symptoms: Sneezing, runny or stuffy nose, coughing, wheezing, shortness of breath.
Skin Symptoms: Itching, redness, swelling, hives, or eczema.
Eye Symptoms: Redness, itching, swelling, and watery eyes.
Digestive Symptoms: Nausea, vomiting, diarrhoea, abdominal pain.
Others: Anaphylaxis, a severe and potentially life-threatening reaction, can cause symptoms like rapid or weak pulse, a drop in blood pressure, difficulty breathing, confusion, loss of consciousness, and even shock.

Types of Allergies

There are several types of allergies, and they can be classified based on their triggers:

Hay Fever (Allergic Rhinitis): Triggered by pollen, dust mites, mould, or animal dander.
Asthma: A condition where allergens can cause the airways to become inflamed and narrowed. Triggers often include pollen, dust mites, mould, animal dander, smoke, cold air, and exercise.
Food Allergies: Triggered by certain foods, with common culprits being peanuts, tree nuts, milk, eggs, wheat, soy, fish, and shellfish.
Drug Allergies: Triggered by certain medications, like penicillin.
Insect Sting Allergies: Caused by stings from insects like bees, wasps, and hornets.
Contact Dermatitis: A skin reaction from contact with allergens or irritants, such as poison ivy, nickel, or certain cosmetics.
Latex Allergy: Triggered by exposure to latex.
Allergic Conjunctivitis: An allergic reaction of the eyes, usually from pollen or animal dander.

Stages of Allergies

Allergies can be understood in stages, particularly when considering the progression of an allergic response:

Sensitisation: The first time an allergic person comes into contact with an allergen, their immune system may react by producing a specific antibody called immunoglobulin E (IgE). This process is called sensitisation. The person might not experience any symptoms during this stage.
Early Phase Reaction: Upon subsequent exposures to the allergen, the allergen will bind to the IgE on the surface of certain cells, causing these cells to release various chemicals. Histamine is one of these chemicals, and its release leads to many immediate symptoms of an allergic reaction, such as itching, redness, and swelling.
Late Phase Reaction: Hours after the initial exposure, other immune cells are attracted to the site, leading to more prolonged symptoms. This can result in chronic symptoms or increased sensitivity to other triggers.
Chronic Stage: The inflammatory response can become chronic with repeated allergens exposure. For instance, in allergic asthma, chronic inflammation can lead to long-term changes in the airways.

Diagnosis of Allergies

Diagnosing allergies typically involves a combination of a detailed patient history, physical examination, and specific tests. The process includes the following:

Medical History: The doctor will ask about the symptoms, their frequency and duration, any potential triggers that might have been noticed, and any family history of allergies.
Physical Examination: The doctor may look for physical signs of allergies, such as nasal congestion, hives, or eczema.
Skin Test (Skin Prick Test): One of the most common allergy tests. A tiny needle introduces small amounts of suspected allergens into the skin. If the patient is allergic, they will develop a raised bump at the test location.
Blood Test: A blood test (like the Radioallergosorbent Test, RAST, or ImmunoCAP) can measure the amount of specific IgE antibodies present when exposed to certain allergens.
Challenge Test: Under supervised conditions, the patient is exposed to a suspected allergen (commonly used for food or medication allergies). This test must be done cautiously due to the risk of severe allergic reactions.
Pulmonary Function Test: Used primarily for asthma diagnosis, it measures how well the lungs work.

Treatment for Allergies

Treatment for allergies can vary depending on the type and severity of the allergy:

Avoidance: The most effective treatment is to avoid the allergen. This might mean keeping your home free of dust mites or pet dander, avoiding certain foods, or staying indoors during high pollen counts.
Medications: These can help treat the symptoms of allergies. Common medications include antihistamines, corticosteroids, decongestants, leukotriene modifiers, and others.
Immunotherapy (Allergy Shots): This involves receiving regular injections of a tiny amount of the allergens that trigger your symptoms. Over time, this can decrease sensitivity to the allergens and provide long-term relief.
Emergency Epinephrine: For people with severe allergies that can cause anaphylaxis, carrying an emergency epinephrine injection (like an EpiPen) can be life-saving.
Sublingual Immunotherapy: Instead of shots, allergen tablets are placed under the tongue, where they dissolve.

Allergies vs. Sensitivities

Both allergies and sensitivities are adverse reactions to substances, but they involve different mechanisms in the body and manifest differently.

Allergies involve the immune system. When an allergic person encounters an allergen, their immune system releases immunoglobulin E (IgE) antibodies. This leads to the release of histamine and other chemicals, which cause allergic symptoms.

Unlike allergies, sensitivities don't involve IgE antibodies. The reactions can be due to various mechanisms, such as enzyme deficiencies, direct nervous system stimulation, or reactions to naturally occurring chemicals in foods.

Sensitivities often involve the digestive system but can also affect other body parts. Symptoms can be vaguer and harder to pinpoint compared to allergic reactions. It can appear hours or even days after exposure, making it sometimes challenging to identify the culprit.

Examples of sensitivities are lactose intolerance (where the body lacks enough of the enzyme lactase to digest lactose) or sensitivity to MSG.

Food Reactions

Food reactions can be due to allergies, sensitivities, or other conditions. Differentiating the type of reaction is crucial for appropriate management:

Food Allergies: Involves the immune system and can lead to severe reactions like anaphylaxis. Common food allergens include peanuts, tree nuts, milk, eggs, wheat, soy, fish, and shellfish.
Food Sensitivities or Intolerances: These are non-allergic reactions to foods. Symptoms are generally less severe than allergic reactions but can still be unpleasant. Examples include lactose intolerance, sensitivity to food additives like sulphites, or reactions to food histamine.
Other Food Reactions: Celiac disease, an autoimmune reaction to gluten, is sometimes mistaken for a food allergy or sensitivity. It involves a different mechanism and can lead to long-term health complications if not appropriately managed.

It's essential to differentiate between these reactions because the management and potential risks differ. For instance, someone with a peanut allergy might have to avoid even trace amounts of peanuts and carry an epinephrine injector. In contrast, someone with lactose intolerance might manage their symptoms by taking lactase supplements or consuming lactose-free dairy products.

What if Allergies are Untreated?

If allergies are left untreated, they can lead to various complications, depending on the type of allergy:

Chronic Symptoms: Persistent symptoms like nasal congestion, cough, or digestive issues can significantly affect quality of life.
Asthma: Allergies increase the risk of developing asthma and can worsen existing asthma.
Sinus Infections: Chronic nasal inflammation or sinusitis can develop from untreated allergic rhinitis.
Ear Infections: Especially in children, untreated allergies can lead to recurrent ear infections due to fluid buildup.
Anaphylaxis: This is a severe, life-threatening allergic reaction that can occur in response to foods, medications, insect stings, or other triggers. If not treated immediately with epinephrine, it can be fatal.
Poor Quality of Life: Chronic symptoms can lead to sleep disturbances, missed work or school days, and reduced overall well-being.