Allergic Reactions: Symptoms, Causes, and Treatment

April 17, 2023

Overview of Allergic Reactions: Symptoms, Causes, and Types

Allergic reactions are the body’s response to a foreign substance, known as an allergen, that it perceives as harmful. These reactions can range from mild to severe and can occur in various parts of the body, including the skin, respiratory system, and digestive system.

Symptoms of Allergic Reactions

  • Skin rash or hives: Swelling and redness of the skin that often appears in the form of raised, red bumps or welts.
  • Itchy eyes, nose, or throat: Itching in these areas is a common symptom of allergic rhinitis (hay fever) and allergic conjunctivitis (eye allergies).
  • Sneezing, runny nose, or nasal congestion: These symptoms are also common in allergic rhinitis.
  • Wheezing, coughing, or difficulty breathing: These symptoms can occur in people with asthma or allergic bronchitis.
  • Abdominal pain, diarrhea, or vomiting: These symptoms can occur in people with food allergies or allergies to certain medications.
  • Anaphylaxis: A severe and potentially life-threatening allergic reaction that can cause swelling of the throat and tongue, difficulty breathing, and a drop in blood pressure.

Causes of Allergic Reactions

Allergies occur when the immune system mistakenly identifies a harmless substance as a threat and produces antibodies to fight it. Some common allergens include:

  • Pollen: Pollen from trees, grass, and weeds can cause allergic rhinitis and asthma.
  • Mold: Mold spores can cause allergic rhinitis and asthma.
  • Animal: Pet dander, saliva, and urine can cause allergic reactions in some people.
  • Foods: Certain foods, such as peanuts, tree nuts, fish, and shellfish, can cause allergic reactions.
  • Medications: Certain medications, such as antibiotics and aspirin, can cause allergic reactions in some people.

Types of Allergic Reactions

Allergic reactions can be classified into two main types:

  • IgE-mediated: These reactions are caused by the production of IgE antibodies and are often immediate, occurring within minutes to a few hours after exposure to the allergen. Examples include hives, anaphylaxis, and allergic asthma.
  • Non-IgE-mediated: These reactions are not caused by the production of IgE antibodies and are often delayed, occurring several hours to several days after exposure to the allergen. Examples include eczema and food allergies.

Understanding the symptoms, causes, and types of allergic reactions is important in the diagnosis and treatment of allergies. If you suspect you have an allergy, it is important to consult a healthcare professional for proper diagnosis and treatment.

Common Allergens and Triggers

An allergen is a substance that can cause an allergic reaction in some individuals. Allergens can come in many forms, including pollen, mold, animal dander, certain foods, and certain medications. Understanding common allergens and triggers can help individuals identify and avoid potential sources of allergic reactions.

Pollen Allergies

Pollen is a common allergen that can cause allergic rhinitis (hay fever) and asthma. Pollen allergies are seasonal and are usually caused by tree, grass, and weed pollens.

Common Tree Pollens

  • Oak
  • Birch
  • Elm
  • Maple

Common Grass Pollens

  • Rye
  • Bermuda
  • Timothy
  • Johnson

Common Weed Pollens

  • Ragweed
  • Sagebrush
  • Pigweed
  • Lamb’s-quarters

Mold Allergies

Mold is a common allergen that can cause allergic rhinitis and asthma. Mold can be found both indoors and outdoors and can grow on a variety of surfaces, including walls, floors, and ceilings.

Animal Allergies

Animal, such as cats, dogs, and birds, can cause allergic reactions in some people through their dander, saliva, and urine.

Food Allergies

Certain foods, such as peanuts, tree nuts, fish, and shellfish, can cause allergic reactions. These reactions can range from mild, such as hives, to severe, such as anaphylaxis.

Medication Allergies

Certain medications, such as antibiotics and aspirin, can cause allergic reactions in some people. These reactions can range from mild, such as hives, to severe, such as anaphylaxis.

It is important to note that not all individuals will have an allergic reaction to every allergen. Also, the severity of allergic reactions can vary from person to person. If you suspect you have an allergy, it is important to consult a healthcare professional for proper diagnosis and treatment.

Diagnosis and Testing for Allergies

Allergies can be difficult to diagnose because symptoms can be similar to those of other conditions and can vary in severity from person to person. A healthcare professional can help determine if you have an allergy by taking a detailed medical history, performing a physical examination, and conducting diagnostic tests.

Medical History and Physical Examination

During the medical history and physical examination, the healthcare professional will ask about your symptoms, when they occur, and what seems to trigger them. They will also examine your skin, eyes, nose, and lungs to look for signs of allergic reactions.

Diagnostic Tests

Diagnostic tests for allergies can include:

Skin Testing

  • Skin prick test: A small amount of the suspected allergen is placed on the skin and then a small prick is made on the skin. If a raised, red bump or wheal develops at the site, it is likely that you are allergic to that substance.
  • Intradermal test: A small amount of the suspected allergen is injected under the skin. If a raised, red bump or wheal develops at the site, it is likely that you are allergic to that substance.

Blood Testing

  • ImmunoCAP or RAST: Blood is drawn and then sent to a laboratory to measure the level of allergen-specific IgE antibodies in your blood. High levels of IgE antibodies to a specific allergen suggest that you are allergic to that substance.

Other Tests

  • Allergy challenge test: This test is performed in a controlled environment, such as a hospital or clinic, and involves exposing you to increasing levels of the suspected allergen to see if a reaction occurs.
  • Nasal smear: This test is used to look for eosinophils, a type of white blood cell that increases in number during an allergic reaction, in the mucus of your nose.

It is important to note that no single test can confirm or rule out an allergy. A combination of tests and a thorough evaluation of symptoms and medical history will be needed to make a proper diagnosis.

If you suspect you have an allergy, it is important to consult a healthcare professional for proper diagnosis and treatment.

Treatment Options for Allergic Reactions

Treatment for allergic reactions depends on the type and severity of the reaction, as well as the underlying cause. The main goal of treatment is to reduce symptoms and prevent future reactions.

Medications

  • Antihistamines: These medications block the effects of histamine, a chemical released by the body during an allergic reaction, and can relieve symptoms such as sneezing, runny nose, and itching.
  • Decongestants: These medications can help relieve nasal congestion by narrowing the blood vessels in the nose.
  • Corticosteroids: These medications can help reduce inflammation and swelling associated with allergic reactions. They are available in various forms, including nasal sprays, inhaled powders, and oral tablets.
  • Leukotriene modifiers: These medications can help reduce inflammation and swelling associated with allergic reactions.
  • Immunomodulators: These medications can help change the way the immune system responds to allergens.

Allergen Immunotherapy

Allergen immunotherapy, also known as allergy shots, can help desensitize you to the allergen that is causing your symptoms. This treatment involves receiving a series of injections containing small amounts of the allergen. Over time, the amount of allergen in the injections is increased, until you are able to tolerate larger amounts of the allergen without having an allergic reaction.

Surgery

  • Nasal polypectomy: This surgery is done to remove polyps, noncancerous growths in the nasal passages, that can block breathing and cause a stuffy nose.
  • Septoplasty: This surgery is done to correct a deviated septum, a condition in which the wall between the nostrils is bent or shifted, that can block breathing and cause a stuffy nose.

It is important to note that not all treatment options will work for everyone. Your healthcare professional will work with you to find the treatment that is best for you.

It is also important to remember that avoiding allergens and triggers, when possible, is an essential part of managing allergic reactions.

If you suspect you have an allergy, it is important to consult a healthcare professional for proper diagnosis and treatment.

Prevention and Management of Allergic Symptoms

Preventing and managing allergic symptoms can help improve quality of life and prevent severe reactions. In addition to medical treatment, there are several lifestyle and home management strategies that can help reduce symptoms and prevent future allergic reactions.

Avoiding Allergens and Triggers

  • Know your allergens: Identify the allergens that cause your symptoms and try to avoid them.
  • Check pollen counts: During allergy season, check local pollen counts and try to stay indoors on days when the counts are high.
  • Use air conditioning: Use air conditioning to cool your home and car, as it filters and circulates the air.
  • Use a HEPA filter: Use a HEPA (high-efficiency particulate air) filter in your home to remove allergens from the air.
  • Keep windows and doors closed: Keep windows and doors closed to keep allergens out of your home.

Managing Symptoms

  • Use over-the-counter medications: Use over-the-counter antihistamines and decongestants as directed to relieve symptoms.
  • Use nasal irrigation: Use a saline nasal spray or neti pot to rinse out your nasal passages and remove allergens.
  • Use humidifiers: Use humidifiers to add moisture to the air and help relieve dry, stuffy noses.
  • Wear a mask: Wear a mask when doing outdoor activities to help reduce the amount of allergens that you inhale.

Allergy-proofing your home

  • Remove carpeting: Carpeting can trap allergens and should be removed if possible.
  • Use allergen-proof covers: Use allergen-proof covers on mattresses, pillows, and box springs to reduce exposure to dust mites.
  • Keep your home clean: Dust and vacuum regularly to remove allergens from your home.
  • Wash bedding: Wash bedding and curtains in hot water once a week to remove allergens.

It is important to work with your healthcare professional to develop an allergy management plan that is right for you. Remember that avoiding allergens and triggers, when possible, is an essential part of managing allergic reactions.

If you suspect you have an allergy, it is important to consult a healthcare professional for proper diagnosis and treatment.

Sources & references used in this article: