What are allergies?
Allergies refer to a range of conditions caused by an overactive immune system’s sensitivity to typically harmless substances in the environment. These substances, known as allergens, can be found in dust mites, pollen, insects, ticks, mold, food, and certain medications.
Allergens can be inhaled, ingested, or enter through the skin. In the case of an allergy, the immune system produces antibodies that identify a specific allergen as harmful. When exposed to the allergen, the immune system’s reaction can range from mild to severe, affecting the mucous membranes, skin, digestive system, and respiratory system.
What are allergic reactions?
Allergic reactions begin in the immune system as a response to allergens. When a person comes into contact with an allergen, the immune system may overreact by producing antibodies that “attack” the allergen. Upon encountering the allergen, the immune system initially reacts by producing specific antibodies called immunoglobulin E (IgE). IgE antibodies are specific to each allergen and, once formed, they bind to mast cells and basophils. Upon subsequent exposure to the same allergen, histamine and other mediators of hypersensitivity are released. When histamine release is triggered by an allergen, it results in inflammation (redness and swelling), which can be quite uncomfortable. Similar reactions can occur with certain chemicals and food additives.
The symptoms of an allergic reaction will vary depending on the type and amount of allergen encountered and how the immune system responds to the allergic trigger. A person may experience symptoms such as itching, runny nose, watery or itchy eyes, throat irritation, and other symptoms.
How allergic reactions differ from hypersensitivity or intolerance
The fundamental difference between allergies, hypersensitivity, and intolerance lies in the fact that allergies involve an immune system response to a substance, while sensitivity does not involve an immune response. Intolerance is characterized by a deficiency of enzymes needed to digest certain foods (e.g., lactose intolerance). Since a range of symptoms can be associated with allergies, hypersensitivity, or intolerances, it is necessary for a doctor to evaluate the specific situation through appropriate tests to determine the underlying cause.
Who can have an allergic reaction?
Allergic reactions can affect anyone, regardless of age, gender, race, or socioeconomic status. Generally, allergies are more common in children. However, allergies can occur for the first time at any age or recure after many years of remission. Hormones, stress, smoke, perfumes, or environmental agents can also play a role in the development or serious manifestations of allergies.
Genetic predisposition – Atopy is a genetic predisposition to develop allergic diseases. When atopic individuals are exposed to allergens, they may develop an immune reaction that leads to allergic inflammation. These individuals may experience symptoms such as runny nose and watery eyes, resulting in allergic rhinitis and conjunctivitis. Allergic skin reactions can manifest as rashes or eczema. A person with allergies may also develop asthma symptoms.
Environmental factors – Among the extensively studied environmental factors that influence allergies are airborne allergens: dust mites, pollen, molds, and animal dander.
Age and allergy development – Many people outgrow their allergies in their 20s and 30s as they become tolerant to allergens, particularly food allergens such as milk, eggs, and grains. However, it is possible to develop an allergy at any age, even to something that a person was not previously allergic to.
Allergies are more likely to develop in people who have a family history of asthma or allergies, such as hay fever or eczema.
The most common types of allergies
Food allergy – There are different types of allergic reactions to food. There are differences between allergies mediated by IgE antibodies, non-IgE allergies, and food intolerances.
Gluten allergy – Gluten is a specific type of plant protein found in wheat, rye, and barley. Symptoms may include bloating, gas, diarrhea, weight loss, rash, redness, and fatigue.
Sun allergy – It causes a skin rash after exposure to sunlight or other sources of ultraviolet (UV) radiation.
Pollen allergy – Pollen is one of the most common triggers of seasonal allergies. Experts commonly refer to it as “seasonal allergic rhinitis.”
Ambrosia allergy – Ragweed pollen is causing allergies in an increasing number of people. The most common symptoms of ragweed allergy are coughing, runny nose, and throat itchiness.
Dust mite allergy – Dust mite allergy is an allergic reaction to tiny insects that typically live in house dust. Signs of dust mite allergy include those common to hay fever, such as sneezing and a runny nose. Many people with dust mite allergy also experience asthma symptoms, such as wheezing and difficulty breathing.
Cat and dog allergy – Allergies to furry pets are common. It is important to note that there are no allergy-free (hypoallergenic) dog or cat breeds.
Insect sting allergy – Bees, wasps, hornets, and certain types of ants are the most common insects that cause allergic reactions. Insects that cannot sting can also cause allergic reactions. Cockroaches and dust mites are the most common indoor insects that can trigger allergy and asthma symptoms.
Penicillin allergy – Penicillin allergy is an immune system reaction to the antibiotic penicillin. Common symptoms of penicillin allergy include hives, rash, and itching. Severe reactions include anaphylaxis, a life-threatening condition that affects multiple systems.
Respiratory allergies – They mainly involve allergens found indoors (such as dust mites and house dust) and outdoors (such as pollen and molds). Seasonal allergies, such as allergic rhinitis, are a type of respiratory allergy.
Mold (fungus) allergy – Since molds grow everywhere, both indoors and outdoors, allergic reactions to molds can occur year-round.
Medication allergy – True medication allergies occur in only a small number of people. Most adverse reactions to drugs are not allergies but rather side effects of the medication. The diagnosis of the cause of a drug reaction is usually based on the patient’s history and symptoms. Sometimes, skin testing for drug allergies is performed.
Latex allergy – In most cases, latex allergy develops after repeated exposures to latex. Symptoms of latex allergy can include rash, itching, runny nose, and difficulty breathing. Symptoms typically begin within minutes of exposure to latex-containing products (such as gloves, condoms).
Typical symptoms of allergic reaction
Typical symptoms of allergic reactions can vary depending on the trigger and can affect the respiratory tract, sinuses and nasal passages, skin, and digestive system. Allergic reactions can range from mild to severe, and in some severe cases, allergies can cause life-threatening anaphylaxis.
Symptoms of pollen allergy may include:
-Sneezing
-Itchy nose, eyes, or lips
-Runny or stuffy nose
-Red, swollen, watery eyes (conjunctivitis)
Symptoms of food allergy:
-Swelling of the lips, tongue, face, or throat
-Hives
-Anaphylaxis
Symptoms of insect sting allergy may include:
-Large swelling (edema) at the site of the sting
-Itching or hives throughout the body
-Coughing, chest tightness, shortness of breath
-Anaphylaxis
Symptoms of drug allergy:
-Hives
-Itchy skin
-Rash
-Facial swelling
-Anaphylaxis
-Atopic dermatitis
-Eczema
Anaphylaxis (severe allergic reaction)
Some types of allergies, including food allergies and insect stings, can cause a life-threatening severe allergic reaction known as anaphylaxis. This is a condition in which tissues, including those in the throat, swell. Anaphylaxis can lead to anaphylactic shock, which is accompanied by a sudden drop in blood pressure. Each person may experience different symptoms, which can include:
– Loss of consciousness
– Shortness of breath
– Difficulty breathing
– Skin rash
– Fainting
– Rapid, weak pulse
– Nausea and vomiting
Anaphylactic shock can be caused by an allergic reaction to medication, food, serum, insect venom, allergen extracts, or chemicals. Some individuals who are aware of their allergic reactions or triggers carry an emergency anaphylaxis kit that contains an injectable epinephrine (a medication that stimulates the adrenal glands and increases heart rate and strength of contractions).
Diagnosis and tests for allergies
Physical examination and medical history – The doctor will ask detailed questions about the symptoms, their timing, intensity, duration, previous occurrences, and family history of allergies. Keeping a detailed symptom diary and noting potential triggers is advised. For example, if someone has a food allergy, the doctor may ask them to record any allergic reactions after consuming certain foods.
The doctor mainly tests the patient for allergies he suspects, these are blood tests and a skin test (prick probe).
Blood test – Specific blood tests are conducted to measure the presence of IgE antibodies, which indicate an allergic response. Elevated levels of IgE suggest an allergy.
Skin test (Prick test) – Small amounts of proteins from common allergens are applied to the skin using tiny punctures or pricks. If an allergy is present, an allergic reaction will occur at the test site.
Tests with oral intake of allergens – Food testing is performed by gradually consuming the suspected allergenic food in increasing amounts under medical supervision to accurately diagnose or rule out a true food allergy.
If the doctor suspects that the symptoms are caused by something other than an allergy, additional tests may be conducted to identify or rule out other health conditions.
Treatment of allergies
Treating allergies is often long-term and complex and may include:
-Avoiding allergens: The doctor provides advice on how to avoid allergy triggers. This is generally the most important step in preventing allergic reactions and reducing symptoms.
-Medications: Depending on the type of allergy, medications can help reduce the immune system’s response and alleviate symptoms. These can be over the counter or prescription medications in the form of pills, liquids, nasal sprays, or eye drops. Antihistamines can relieve or control symptoms and are taken before allergen exposure. Corticosteroids are used to treat inflammation and swelling caused by allergies, as well as allergic asthma. Intranasal corticosteroid sprays are effective in treating moderate to severe allergic rhinitis. Oral corticosteroids, such as tablets or syrups, have a similar purpose to nasal sprays. Combination therapy of corticosteroids and antihistamines is used for moderate to severe allergic rhinitis.
-Immunotherapy: For severe allergies or allergies that are not fully resolved with other treatments, the doctor may recommend allergen immunotherapy. This treatment involves a series of injections of purified allergen extracts, usually given over several years. Another form of immunotherapy is sublingual tablets that dissolve under the tongue.
-Epinephrine injection: Individuals prone to severe allergic reactions should have an epinephrine auto-injector with them, as it can help reduce symptoms until emergency assistance arrives.
-Food allergy recommendations: Natural foods suitable for most people with allergies include poultry, legumes, grains (except wheat), fruits, and vegetables. Although dietary restrictions may seem daunting, these foods can provide a varied and nutritious diet. For someone with multiple allergies, making safe food choices can be challenging (e.g., meat protein allergy). Therefore, it is recommended to create a meal plan based on medical findings and advice.
In terms of diet, it is important to avoid common allergenic foods such as cow’s milk, eggs, peanuts, soy, peas, lentils, nuts (walnuts, almonds, hazelnuts, pistachios), shellfish, and wheat.
Prevention of allergies
Prevention of allergic reactions depends on the type of allergy.
Some general measures to consider include:
-Avoiding known allergens: Even if you are treating allergy symptoms, try to avoid triggers. For example, if you are allergic to pollen, stay indoors with closed windows and doors when pollen counts are high. If you are allergic to dust mites, regularly dust, vacuum, and wash bedding frequently.
-Keep a diary: When trying to identify what causes or worsens your allergic symptoms, keep track of your activities and what you eat, when symptoms occur, and what seems to help. This can help identify allergy triggers.
If you have had a severe allergic reaction, wearing a medical bracelet or necklace can alert others that you have a serious allergy in case you have a reaction and are unable to communicate. Additionally, always carry an epinephrine auto-injector with you.
Prognosis / Perspective
Currently, there is no cure for allergies, so living with allergies can be challenging. Symptoms can range from mild to severe. Allergies generally last as long as you are exposed to the allergen. When you are no longer near the allergen, symptoms should disappear within a few hours. However, if you suffer from respiratory allergies, symptoms can last for several days or longer due to constant exposure to pets, dust mites, and pollen. Nevertheless, there are medications available that can help alleviate symptoms. Avoiding allergen triggers or reducing contact with them can help prevent allergic reactions. Over time, immunotherapy can significantly reduce allergic reactions.
When to visit a doctor?
If there is suspicion of an allergy, it is important not to wait for the symptoms to go away on their own. If the symptoms persist for more than a week or two, or if they tend to recur at certain times of the year, it is advisable to schedule an appointment with an allergist who can conduct tests to determine whether you have an allergy.
Signs of an emergency doctor
In case of anaphylaxis, immediate medical assistance is necessary. The symptoms may include:
- Loss of consciousness
- Drop in blood pressure
- Shortness of breath
- Swelling
- Skin rash
- Rapid pulse
- Nausea and vomiting
If you have previously experienced a severe allergic reaction or any symptoms of anaphylaxis, it is essential to seek medical attention.
Living with allergies
Some symptoms can be managed by individuals themselves:
- Symptoms of allergic rhinitis: Nasal and sinus irrigation with saline solution.
- Household allergy symptoms: Reduce exposure to dust mites or pet dander by regularly washing bedding and stuffed toys in hot water, maintaining low humidity, using a vacuum cleaner with a fine filter such as a high-efficiency particulate air (HEPA) filter, and removing carpets.
- Mold allergy symptoms: Prevent moisture buildup in the bathroom and kitchen by using exhaust fans and dehumidifiers.
- Regular use of therapy: By using specific medications or immunotherapy, it is possible to significantly alleviate or eliminate allergy symptoms.
- Proper nutrition: Individuals with allergies should be careful in choosing their food, especially those who have allergic reactions to specific foods.
- Always carry an epinephrine auto-injector with you and inject yourself if symptoms occur.
Strategies for coping with life with allergies
Here are some good habits that will help with allergies throughout the year:
- Strive to stay in a clean environment with minimal dust, mites, and mold.
- At the time of flowering, avoid staying outside when pollen concentration is greatest.
- Close windows and wash clothes worn outside to prevent pollen from entering your home.
- Always carry medications that help alleviate allergy symptoms (such as nasal spray).
- Consider using natural remedies for allergies, such as honey, bromelain found in pineapple, probiotics, and vitamin C. However, it’s important to consult a doctor before trying these remedies.
- Some studies suggest that people with allergic rhinitis may benefit from acupuncture.
