What Should You Do if You Think You Have Allergies?
Start by tracking your symptoms and potential triggers in a journal. Over-the-counter antihistamines like cetirizine or loratadine can provide initial relief. If symptoms persist or significantly affect your quality of life, schedule an appointment with an allergist for proper testing and a personalized treatment plan.
The first step in managing allergies is identifying what triggers your symptoms. Keep a detailed log of when symptoms occur, what you were doing, and your environment. Note whether symptoms happen indoors or outdoors, during specific seasons, or after eating certain foods. This information will be invaluable when you see a healthcare provider. The American College of Allergy, Asthma, and Immunology recommends starting with a primary care visit to rule out other conditions that mimic allergy symptoms.
While waiting for a medical evaluation, several over-the-counter options can help. Second-generation antihistamines like cetirizine (Zyrtec), loratadine (Claritin), and fexofenadine (Allegra) effectively reduce sneezing, itching, and runny nose without significant drowsiness. Nasal saline rinses can flush allergens from nasal passages. For nasal congestion, intranasal corticosteroid sprays like fluticasone (Flonase) are considered the most effective first-line treatment by the American Academy of Allergy, Asthma, and Immunology.
According to the AAAAI, intranasal corticosteroids are the single most effective medication class for allergic rhinitis
What Are Allergies and How Do They Develop?
Allergies occur when your immune system mistakenly identifies a harmless substance as dangerous and mounts a defensive response. This process involves the production of immunoglobulin E antibodies, which trigger the release of histamine and other chemicals that cause allergy symptoms like sneezing, itching, and swelling.
Your immune system normally protects you from genuinely harmful invaders like bacteria and viruses. In people with allergies, the immune system produces IgE antibodies against substances that are typically harmless, such as pollen, pet dander, or certain foods. When you encounter the allergen again, these IgE antibodies recognize it and signal mast cells to release histamine and other inflammatory mediators. This cascade of chemical signals produces the familiar symptoms of an allergic reaction.
Allergies develop through a process called sensitization. During your first exposure to an allergen, your immune system may quietly begin producing IgE antibodies without causing symptoms. Subsequent exposures trigger progressively stronger immune responses, eventually producing noticeable symptoms. This is why someone can eat a food for years before suddenly developing an allergy to it. The World Health Organization estimates that allergic diseases affect 30 to 40 percent of the global population, making them one of the most common chronic conditions worldwide.
The WHO estimates allergic diseases affect 30 to 40 percent of the global population
What Are the Most Common Types of Allergies?
The most common allergy types are seasonal allergic rhinitis (hay fever), perennial allergic rhinitis from indoor allergens, food allergies, drug allergies, insect sting allergies, and contact dermatitis. Each type involves different allergens and may require different management strategies.
Seasonal allergic rhinitis, commonly called hay fever, affects approximately 81 million Americans annually according to the Asthma and Allergy Foundation of America. Tree pollen peaks in spring, grass pollen in late spring and summer, and ragweed pollen in fall. Perennial allergic rhinitis persists year-round and is typically caused by dust mites, mold spores, cockroach droppings, or pet dander. These indoor allergens can be particularly difficult to avoid since they accumulate in homes and workplaces.
Food allergies affect approximately 32 million Americans, including 5.6 million children under age 18. The most common food allergens are milk, eggs, peanuts, tree nuts, wheat, soy, fish, shellfish, and sesame. Food allergies can range from mild oral itching to severe anaphylaxis. Drug allergies most commonly involve penicillin and related antibiotics, nonsteroidal anti-inflammatory drugs like ibuprofen, and certain chemotherapy agents. Contact dermatitis involves skin reactions to substances like nickel, latex, or poison ivy.
The AAFA reports that seasonal allergic rhinitis affects approximately 81 million Americans each year
- Seasonal allergic rhinitis (hay fever): pollen from trees, grasses, and weeds
- Perennial allergic rhinitis: dust mites, mold, pet dander, cockroaches
- Food allergies: peanuts, tree nuts, milk, eggs, shellfish, wheat, soy, fish, sesame
- Drug allergies: penicillin, NSAIDs, sulfonamides, chemotherapy agents
- Insect sting allergies: bees, wasps, hornets, yellow jackets, fire ants
- Contact dermatitis: nickel, latex, poison ivy, fragrances, preservatives
What Are the Symptoms of Allergies?
Allergy symptoms vary depending on the allergen and how you are exposed. Respiratory allergies cause sneezing, runny nose, congestion, and itchy eyes. Food allergies can cause hives, swelling, digestive upset, and in severe cases, anaphylaxis. Skin allergies produce redness, itching, and rashes.
Allergic rhinitis symptoms include sneezing, clear watery nasal discharge, nasal congestion, postnasal drip, itchy nose and throat, and watery itchy eyes. These symptoms can significantly impact quality of life, affecting sleep, concentration, work productivity, and school performance. The allergic salute — the upward rubbing of the nose with the palm — and allergic shiners — dark circles under the eyes from nasal congestion — are classic physical signs that suggest allergies rather than a viral infection.
Food allergy symptoms typically appear within minutes to two hours after eating the offending food. Mild symptoms include tingling or itching in the mouth, hives or eczema, and abdominal pain or diarrhea. Severe food allergy reactions can progress to anaphylaxis, a life-threatening emergency characterized by throat swelling, difficulty breathing, rapid pulse, dizziness, and a dangerous drop in blood pressure. The CDC reports that food allergy-related emergency department visits have increased significantly over the past two decades.
How Are Allergies Diagnosed?
Allergists diagnose allergies through a combination of medical history, physical examination, and specific tests. Skin prick testing is the most common method, providing results within 15 to 20 minutes. Blood tests measuring allergen-specific IgE levels offer an alternative when skin testing is not appropriate.
Skin prick testing involves placing small drops of purified allergen extracts on your forearm or back and then lightly pricking the skin through each drop. A positive result appears as a raised, red, itchy bump called a wheal within 15 to 20 minutes. Skin prick tests can evaluate dozens of allergens simultaneously and have good sensitivity and specificity. The AAAAI considers skin prick testing the gold standard for diagnosing IgE-mediated allergies.
Blood tests, specifically serum-specific IgE tests (formerly called RAST tests), measure the amount of IgE antibodies your blood produces in response to specific allergens. These tests are useful when skin testing cannot be performed — for example, in patients taking antihistamines that cannot be stopped, those with severe eczema covering large skin areas, or patients at high risk of anaphylaxis from skin testing. Component-resolved diagnostics, a newer approach, can identify specific proteins within an allergen source to better predict clinical reactivity.
What Are the Best Treatment Options for Allergies?
Allergy treatment follows a stepwise approach: allergen avoidance first, then medications to control symptoms, and immunotherapy for long-term desensitization. Antihistamines, nasal corticosteroids, and leukotriene modifiers are the primary medications. Immunotherapy through shots or sublingual tablets can provide lasting relief.
Allergen avoidance is the foundation of allergy management, though it is not always practical. For dust mite allergies, encasing mattresses and pillows in allergen-proof covers, washing bedding weekly in hot water, and maintaining indoor humidity below 50 percent can significantly reduce exposure. For pollen allergies, monitoring local pollen counts, keeping windows closed during high-pollen days, showering after outdoor activities, and using HEPA air purifiers can help reduce symptoms.
When avoidance alone is insufficient, medications provide symptom relief. Second-generation antihistamines like cetirizine, loratadine, and fexofenadine are first-line treatments with minimal side effects. Intranasal corticosteroids such as fluticasone, mometasone, and budesonide are the most effective single medication class for allergic rhinitis. Leukotriene receptor antagonists like montelukast (Singulair) can help patients with both allergies and asthma. For severe or refractory symptoms, allergen immunotherapy offers the potential for long-term disease modification.
Allergen immunotherapy gradually exposes your immune system to increasing doses of specific allergens over three to five years. Subcutaneous immunotherapy (allergy shots) has been used for over a century and is effective for environmental and venom allergies. Sublingual immunotherapy tablets, available for grass pollen, ragweed, and dust mites, offer a convenient at-home alternative. Studies published in JAMA show that immunotherapy can reduce symptom severity by 30 to 40 percent and decrease medication needs.
A systematic review in JAMA found that allergen immunotherapy reduces allergy symptom severity by 30 to 40 percent compared to placebo
When Should You See a Doctor for Allergies?
See a doctor if over-the-counter medications do not adequately control your symptoms, if allergies interfere with sleep or daily activities, if you develop signs of asthma like wheezing or chest tightness, or if you have ever experienced a severe allergic reaction requiring emergency care.
While mild allergies can often be managed with over-the-counter treatments, certain situations warrant professional evaluation. An allergist can perform comprehensive testing to identify your specific triggers, develop a personalized avoidance plan, and prescribe more targeted therapies. Referral to an allergist is particularly important if you have multiple allergies, allergies combined with asthma, suspected food or drug allergies, or recurrent sinus infections that may be allergy-related.
Seek immediate emergency care for any signs of anaphylaxis, including difficulty breathing, throat tightening, widespread hives, rapid pulse, dizziness, or fainting after allergen exposure. If you have a known risk of anaphylaxis, your doctor should prescribe epinephrine auto-injectors and create an anaphylaxis action plan. The AAAAI recommends that all patients who have experienced anaphylaxis carry two epinephrine auto-injectors at all times and wear medical identification jewelry.
How Can You Prevent Allergic Reactions?
Prevention focuses on minimizing exposure to known allergens through environmental controls, dietary vigilance for food allergies, and medication use before anticipated exposure. Allergen immunotherapy is the only treatment that can modify the underlying disease process and potentially prevent new allergies from developing.
Environmental control measures are the cornerstone of allergy prevention. For indoor allergens, use HEPA vacuum filters, remove carpeting where possible, keep pets out of bedrooms, control humidity to prevent mold growth, and regularly clean air ducts and replace HVAC filters. For outdoor allergens, check daily pollen forecasts through the National Allergy Bureau, limit outdoor activities during peak pollen hours (typically early morning), and change clothes and shower after spending time outdoors.
For food allergies, careful label reading is essential since the Food Allergen Labeling and Consumer Protection Act requires clear labeling of the nine major allergens. When dining out, communicate your allergies clearly to restaurant staff and ask about ingredients and cross-contamination risks. Research from the LEAP study published in the New England Journal of Medicine demonstrated that early introduction of peanuts to high-risk infants can reduce the risk of developing peanut allergy by up to 81 percent, changing prevention guidelines for food allergies.
The LEAP trial showed early peanut introduction reduced peanut allergy risk by 81 percent in high-risk infants
