Allergies: Causes, Symptoms, Diagnosis, Treatment, and Prevention

How Common are Allergies?

Allergies are incredibly common, affecting up to 30% of adults and 40% of children worldwide. They can be mild or severe and can significantly impact a person’s quality of life. In some cases, severe allergic reactions, such as anaphylaxis, can also be life-threatening and require immediate medical attention.

• Drug Allergy: This type of allergy occurs when the immune system overreacts to a medication. It is also called drug hypersensitivity or drug-induced allergy. Symptoms can range from mild, such as skin rash or itching, to severe, such as anaphylaxis, which is a life-threatening allergic reaction. Examples of medications that can cause drug allergies to include antibiotics, painkillers, and chemotherapy drugs.
• Food Allergies: This type of allergy occurs when the immune system overreacts to a particular food. It is also called food hypersensitivity or food-induced allergy. Symptoms can range from mild, such as hives or itching, to severe, such as anaphylaxis. Common food allergens which include peanuts, tree nuts, shellfish, fish, milk, eggs, wheat, and soy.
• Contact Dermatitis: This type of allergy occurs when the skin comes into contact with a substance that triggers an allergic reaction. It is also called allergic contact dermatitis. Symptoms typically include a red, itchy rash that develops on the skin. Common triggers include poison ivy, nickel, latex, and certain fragrances or chemicals.
• Latex Allergy: This type of allergy occurs when the immune system overreacts to latex, which is a natural rubber material found in many products, such as gloves, condoms, and balloons. Symptoms can range from mild, such as skin rash or hives, to severe, such as anaphylaxis.
• Allergic Asthma: This type of allergy occurs when the immune system overreacts to an allergen, such as pollen, dust mites, or pet dander, causing inflammation and narrowing of the airways in the lungs. Symptoms typically include wheezing, coughing, and difficulty breathing.
• Seasonal Allergies: This type of allergy occurs when the immune system overreacts to pollen from trees, grasses, and weeds during specific times of the year. It is also called hay fever or allergic rhinitis. Symptoms typically include a runny nose, sneezing, and itchy eyes.
• Animal Allergy: This type of allergy occurs when the immune system overreacts to proteins found in an animal’s skin cells, saliva, or urine. It can be triggered by exposure to pet dander, such as from cats, dogs, or rodents. Symptoms typically include sneezing, runny nose, and itchy eyes.
• Anaphylaxis: This is a severe, life-threatening allergic reaction that can be caused by any type of allergen, including food, medications, insect stings, or latex. Symptoms can include difficulty breathing, swelling of the face and throat, rapid pulse, and dizziness. Immediate medical attention is necessary to prevent potentially fatal complications.
• Allergy to Mold: This type of allergy occurs when the immune system overreacts to mould spores that are present in the air or on surfaces, such as in damp environments or on decaying vegetation. Symptoms can include sneezing, runny nose, itchy eyes, and skin rash. In some cases, it can trigger asthma symptoms.

• Itchy, watery eyes
• Runny or stuffy nose
• Sneezing
• Coughing
• Rash or hives
• Swelling, particularly around the face and eyes
• Shortness of breath or wheezing
• Nausea or vomiting
• Abdominal pain or cramping

• Drug Allergy: Symptoms can range from mild, such as a skin rash or itching, to severe, such as anaphylaxis. Other symptoms may include fever, joint pain, and swelling.
• Food Allergies: Symptoms can range from mild, such as hives or itching, to severe, such as anaphylaxis. Other symptoms may include digestive issues such as nausea, vomiting, and diarrhea.
• Contact Dermatitis: Symptoms include a red, itchy rash that develops on the skin. The rash may be raised or blistered and can occur on any of the parts of the body that has come into contact with the allergen.
• Latex Allergy: Symptoms can range from mild, such as a skin rash or itching, to severe, such as anaphylaxis. Other symptoms may include difficulty breathing, wheezing, and swelling.
• Allergic Asthma: Symptoms include wheezing, coughing, chest tightness, and shortness of breath. These symptoms are typically triggered by exposure to allergens, such as pollen, dust mites, and also pet dander.
• Seasonal Allergies: Symptoms typically include a runny nose, sneezing, and itchy eyes. These symptoms are typically triggered by exposure to pollen from trees, grasses, and weeds during specific times of the year.
• Animal Allergy: Symptoms typically include sneezing, runny nose, and itchy eyes. These symptoms are typically triggered by exposure to proteins found in an animal’s skin cells, saliva, or urine.
• Anaphylaxis: Symptoms can include difficulty breathing, swelling of the face and throat, rapid pulse, and dizziness. Anaphylaxis is a medical emergency and thus requires immediate treatment with epinephrine.
• Allergy to Mold: Symptoms can include sneezing, runny nose, itchy eyes, and skin rash. In some cases, it can trigger asthma symptoms. These symptoms are typically triggered by exposure to mold spores that are present in the air or on surfaces.

Allergies are caused by an overactive immune system that identifies harmless substances, called allergens, as harmful and triggers an allergic reaction. The immune system produces antibodies called immunoglobulin E (IgE), which bind to the allergen and cause the release of chemicals, such as histamine, in the body. These chemicals cause inflammation and various symptoms, such as itching, sneezing, and difficulty breathing.

Common allergens include pollen, dust mites, mold spores, pet dander, insect stings, certain foods, and medications. Allergies can also be triggered by environmental factors, such as pollution or cigarette smoke, and lifestyle factors, such as stress and lack of sleep.

Allergies are not contagious, meaning that they cannot be spread from person to person through physical contacts, such as touching or kissing. However, some allergens, such as certain viruses or bacteria, can be contagious and may trigger an allergic reaction in some individuals. For example, the common cold virus can trigger asthma symptoms in people with allergic asthma. Additionally, certain allergies, such as food allergies, can be triggered by consuming contaminated food or coming into contact with allergens in food handling or preparation.

• Skin prick test: This involves placing a small amount of the allergen on your skin and then pricking the skin to allow the allergen to enter. If you are allergic to the substance, a small red bump will appear on the skin within 15-20 minutes.
• Patch test: This involves placing a small amount of the allergen on a patch, which is then applied to the skin for 48 hours. If you are allergic to the substance, a rash will appear on the skin where the patch was applied.
• Blood test: This involves testing a sample of your blood for the presence of specific antibodies, such as IgE, which are produced in response to allergens.
• Elimination diet: This involves removing suspected allergens from your diet for a period of time to see if your symptoms improve.
• Oral food challenge: This involves consuming small amounts of the suspected allergen under medical supervision to see if you have a reaction.

The allergy treatment depends on the type and severity of the allergy. Here are some common treatments:

Avoidance

The best way to treat an allergy is to avoid the allergen that triggers the reaction. For example, if you are also allergic to pollen, stay indoors during high pollen count periods or wear a mask when outside.

Allergies Medications

There are several medications that can be used to treat allergies, including:

• Antihistamines: These block the effects of histamine, a chemical which is released by the body during an allergic reaction. They can relieve symptoms such as sneezing, itching, and runny nose.
• Decongestants: These reduce swelling in the nasal passages, making it easier to breathe. They can be used in combination with antihistamines.
• Nasal corticosteroids: These reduce inflammation in the nasal passages and can relieve symptoms such as nasal congestion, runny nose, and sneezing.
• Leukotriene inhibitors: These block the effects of leukotrienes, chemicals released by the body during an allergic reaction. They can help relieve symptoms such as nasal congestion and asthma.
• Immunotherapy: This involves regular exposure to small amounts of an allergen to desensitize the immune system and reduce the severity of the allergic reaction.
• Emergency treatment: Severe allergic reactions, such as anaphylaxis, require immediate emergency treatment with epinephrine. Epinephrine is a medication that can quickly reverse the symptoms of a severe allergic reaction.

The best treatment for allergies depends on the type and severity of the allergy. Mild allergies may be treated with avoidance or over-the-counter medications, while severe allergies may require prescription medications or immunotherapy.

• Avoid allergens: The most effective way to prevent allergies is to avoid the allergen that triggers the reaction. For example, if you are allergic to pollen, stay indoors during high pollen count periods, keep windows and doors closed, and wear a mask when outside.
• Keep your home clean: Dust and vacuum your home regularly to remove allergens such as dust mites and pet dander. Use a high-efficiency particulate air (HEPA) filter to trap allergens in the air.
• Use allergen-proof covers: Use allergen-proof covers on your pillows, mattress, and box spring to keep dust mites out.
• Wash bedding frequently: Wash your bedding, including sheets, pillowcases, and blankets, in hot water once a week to kill dust mites.
• Use a dehumidifier: Use a dehumidifier to reduce humidity in your home, which can help prevent the growth of mold and dust mites.
• Avoid smoking: Avoid smoking and exposure to secondhand smoke, as this can make allergies worse.
• Wear a mask: If you have to be around allergens, such as when doing yard work, wear a mask to protect yourself from inhaling the allergens.
• Take medications as prescribed: If you have been prescribed medications for your allergies, take them as prescribed to help prevent symptoms.

• Virtual consultations: Ongo Care allows patients to schedule virtual consultations with licensed healthcare providers, including doctors and nurse practitioners, who can also diagnose and treat allergies. This can be especially helpful for patients who are unable to visit a doctor in person due to time constraints or mobility issues.
• Prescription refills: If a patient has previously been diagnosed with allergies and needs a prescription refill, they can request a refill through the Ongo Care platform. The healthcare provider will review the request and, if appropriate, issue a prescription refill.
• Allergy education: Ongo Care can provide patients with educational resources on allergies, including information on allergens, symptoms, and treatment options. This can help patients better understand their condition and take steps to manage it.
• Follow-up appointments: Patients can schedule follow-up appointments with their healthcare provider through Ongo Care to monitor their allergy symptoms and adjust their treatment plan as needed.

Frequently Asked Questions