Allergies

Allergies are the result of your immune system mistakenly identifying a substance, called an allergen, as harmful. The immune system then overreacts to the allergen, causing a cascade of responses and symptoms. Allergens are ordinarily harmless to people who don’t have allergies.

Allergens can be things you encounter in daily life like foods, mold spores, or insects. Seasonal allergies are caused by outdoor allergens like pollen that tend to emerge at certain times of the year. Allergies caused by allergens that are present year-round (such as pet dander) are called perennial allergies.

Allergies affect people of all ages and backgrounds. The National Health Interview Survey from the Centers for Disease Control and Prevention (CDC) in 2021 found that:

• Nearly 26 percent of adults had a seasonal allergy. More than 6 percent had a food allergy.
• Close to 19 percent of children have a seasonal allergy and nearly 6 percent have a food allergy.
• White, non-Hispanic adults are more prone to seasonal allergies than other people. Black, non-Hispanic adults are more likely to have food allergies.

What is the difference between a cold and allergies? 

The common cold is an infection of the upper respiratory system that’s caused by a contagious virus. Allergies, on the other hand, are caused by the immune system’s response to an allergen, such as pollen or latex.  

Colds and allergies share several symptoms, including sneezing, nasal congestion, and runny nose. Unlike colds, though, allergies often result in itchy, puffy eyes with dark circles underneath. Allergies generally don’t cause a fever, sore throat, or frequent cough.

Are allergies contagious? 

Allergies are not contagious. Unlike viruses that cause colds, influenza (the flu), or COVID-19, you can’t pass an allergy to someone else by sneezing or coughing. Some allergies are hereditary, though, which means they run in families.

What are allergic diseases?   

Allergic diseases refer to several types of allergies that affect specific areas of the body. For example:  

Allergic rhinitis: Also called hay fever or nasal allergies, allergic rhinitis is caused by allergens (often pollen) that inflame the nose. In fact, rhinitis literally means “inflammation of the nose.” Common symptoms of allergic rhinitis include nasal congestion, runny nose, itchy nose, and itchy, watery eyes. 

Eczema: Eczema refers to a group of inflammatory skin conditions that are often triggered by skin allergies. Common signs of eczema include dry, itchy patches of skin that may crust or blister. Eczema that’s aggravated by allergies is called atopic dermatitis.   

The term allergic diseases may also refer to complications of allergies, such as sinusitis, anaphylaxis, and asthma. (Asthma is a chronic condition that causes inflammation and swelling in the airways, which can lead to wheezing and shortness of breath.)

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Allergies occur when your immune system mistakes an allergen (a typically harmless substance) for a threat that must be resolved. The immune system is an intricate network of cells and organs that work together to defend the body against threats like germs.

To neutralize the perceived threat presented by the allergen, the immune system deploys antibodies (protective proteins) such as immunoglobulin E (IgE) to confront the allergen in question.

If you are allergic to a certain substance, the body produces IgE when you are first exposed to that allergen. This can trigger inflammation and cause cells to release histamine, a chemical that can bind to allergens and result in allergy symptoms like sneezing and runny nose. 

Common allergens in the U.S. include:

• Pollen from trees, grasses, and weeds
• Animal dander (tiny skin cells shed by animals)
• Mold
• Dust mites (a microscopic pest that feeds on dead skin cells)
• Venom from insects
• Latex (a natural chemical used to make rubber products)
• Certain foods, especially peanuts, shellfish, soy, milk, and tree nuts
• Certain medications, especially penicillin and chemotherapy drugs  

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Anyone can develop allergies, but you may have a greater risk of allergic reactions if you:

• Have asthma or eczema
• Have a family history of allergies, asthma, or eczema
• Are frequently exposed to perfume, smoke, or environmental irritants 
• Are a child

It’s important to note that allergies can develop at any age or return after several years of remission. (Remission is a reduction or disappearance of symptoms of a disease or condition.) 

A person’s sex assigned at birth and race/ethnicity may also play a role in allergies. According to the CDC’s 2021 survey:

• Rates of seasonal allergies were higher among women and people assigned female at birth (29.9 percent) than men and people assigned male at birth (21.1 percent).
• Non-Hispanic white people had the highest rates of seasonal allergies (28.4 percent), while non-Hispanic Asian people had the lowest (17 percent). 
• Rates of food allergies were higher among women and people assigned female at birth (7.8 percent) than men and people assigned male at birth (4.6 percent).
• Non-Hispanic Black people had the highest rates of food allergies (8.5 percent), while Hispanic people had the lowest (4.4 percent).

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Allergies are reactions to allergens. Some of the most common types of allergies include:

Pollen allergy

Several types of plants—including trees, weeds, and grasses—produce microspores (small reproductive cells) called pollen. Pollen floats through the air and collects on surfaces in a fine, yellowish dust. (If you live in an area with heavy pollen concentrations, you’ve probably noticed your car covered with the stuff during the spring.)

Pollen can also make its way into your nose, eyes, and lungs and trigger pollen allergies. Pollen is a common cause of seasonal allergic rhinitis.

The three main types of pollen allergies in the U.S. are:

Tree pollen allergies: These tend to occur from February through the spring in most parts of the country. In the South, trees may produce pollen as early as January. Species of trees that release pollen during these months include birch, cedar, elm, hickory, juniper, maple, oak, walnut, and willow, among others.   

Grass pollen allergies: These most often occur between April and June, though grasses may produce pollen year-round in some parts of the South. Most grass pollen allergies are caused by Bahia, Bermuda, Johnson, Timothy, Kentucky blue, and fescue grasses. 

Weed pollen allergies: These typically occur between July and November and are also known as fall seasonal allergies. Ragweed is an especially common type of weed pollen allergy. In fact, an estimated 15 percent of people in the U.S. are allergic to ragweed pollen. Other types of weeds that can trigger fall allergy symptoms include tumbleweed, mugwort, burning bush, pigweed, Russian thistle, sagebrush, and cocklebur weeds.

Drug allergy  

Drug allergies occur when the immune system reacts to a drug or medication as if it were a threat. Medications that are commonly associated with reactions include: 

• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• Penicillin and certain other antibiotics
• Certain chemotherapy drugs
• Insulin (used to treat diabetes)
• Monoclonal antibody drugs (used to treat diseases of the immune system)

True allergies to drugs are uncommon, however. In most cases, a response understood to be a “drug allergy” is actually the result of an adverse reaction to a drug. Adverse reactions don’t involve the immune system. They may occur if you:  

• Take too large of a dose
• Experience an expected or indirect side effect of a drug
• Experience a drug interaction. (This is a side effect that results from combining a medication with another medication or supplement.)
• Experience worsening of an existing condition

Any medication has the potential to cause an allergy or an adverse reaction.

Insect allergy   

Several types of insects that bite or sting can cause allergies. In particular, venom from stinging insects is associated with life-threatening allergic reactions. Stinging insect allergies are responsible for an average of 72 deaths every year in the U.S.

Stinging insects that commonly trigger allergic reactions include:

• Hornets
• Yellow jackets
• Bees
• Wasps
• Fire ants  

Ticks, mosquitoes, and cockroaches can also cause allergies. While they don’t sting or bite, cockroaches can leave behind feces (poop), body parts, eggs, and saliva with proteins that can trigger allergic reactions.

Though not technically an insect, a dust mite is another common cause of allergic reactions. They thrive in warm, humid environments and can be found in household items like mattresses, bedding, curtains, upholstered furniture, and carpeting.

Experiencing an allergic reaction to dust mites is called a dust allergy. You can reduce the number of dust mites in your home by washing bedding in hot water weekly, wet dusting and mopping frequently, and regularly using a vacuum with a high-efficiency particulate air (HEPA) filter.

Food allergy

If your immune system considers a certain type of food as harmful and responds with allergy symptoms, it’s called a food allergy. Food allergies affect more than 20 million adults and children in the U.S. While allergies to food are commonly viewed as a pediatric (children’s) health issue, it’s possible to develop a food allergy at any age. 

There are two types of food allergies:

• Immunoglobin E (IgE) mediated food allergies: These occur when the immune system produces IgE antibodies in response to a certain food. (Most allergies involve IgE antibodies.)
• Non-IgE mediated food allergies: These occur when the immune system reacts to a certain food but does not produce IgE antibodies. 

The most common causes of food allergies in the U.S. include:

• Peanuts
• Milk
• Soy
• Eggs
• Tree nuts (including cashews, pine nuts, pecans, almonds, pistachios, Brazil nuts, walnuts, and macadamia nuts)
• Wheat
• Sesame
• Fish
• Shellfish (including shrimp, lobster, crab, prawns, oysters, clams, scallops, and crawfish)

Some people mistake food allergies for food intolerances. A food intolerance indicates a sensitivity in the digestive tract instead of the immune system. Examples of food intolerances include gluten intolerance and lactose intolerance. Celiac disease involves an immune response to wheat, but it also differs from a wheat allergy.

Pet allergy

Allergies to dogs and cats affect between 10 and 20 percent of the world’s population. Other pets such as birds, rabbits, pigs, hamsters, and horses can also trigger allergies.

Pet fur, hair, or feathers aren’t the source of allergic reactions. Rather, the source is typically a protein found in dander, or dead skin cells. Dander accumulates in fur, hair, or feathers, causing pet allergies. This protein (called “Fel d 1” in cats and “Can f 1” in dogs) can also be found in pet urine and saliva.

But what about hypoallergic pets? (“Hypoallergenic” refers to a substance that is intended to produce fewer allergic reactions.) While some breeds of dogs and cats will shed less hair (and dander) around your home than others, a truly hypoallergenic dog or cat does not exist. It’s still possible to be allergic to a “hypoallergenic” pet’s dander, urine, or saliva.

People who can’t tolerate allergies from furry, hairy, or feathered friends may want to consider having other types of pets, such as fish, turtles, lizards, or snakes.

Mold allergy

Mold is a type of fungus. It can produce tiny spores that float through the air and can be inhaled. Mold generally thrives in damp, humid indoor and outdoor environments, though some types of mold spores can spread in dry, windy weather. Mold allergies are most common between July and early fall.

There are many types of mold, but only a few are known to cause allergy symptoms in the U.S. These include:

• Penicillum
• Alternaria
• Clasdosporium
• Asoergillus  

Latex allergy

Some people are allergic to latex, which is a protein that’s found in rubber trees. These are grown in Southeast Asia and Africa. Many everyday rubber products are made with natural latex, including:

• Bandages
• Foam pillows and mattresses
• Balloons
• Condoms
• Erasers
• Household and medical gloves
• Rubber balls
• Elastic clothing
• Rubber bands
• Dental products, such as orthodontic rubber bands   

Uncommon allergies 

Some people have allergic reactions to substances that don’t affect most other people. Examples of uncommon or rare allergies include:

• Sun allergy (also known as photosensitivity)
• Water allergy (aquagenic urticaria) 
• Sweat allergy (cholinergic urticaria)
• Cold temperature allergy (cold urticaria)
• Allergy to nickel, a type of metal found in some jewelry, coins, eyeglass frames, and phones
• Exercise-induced anaphylaxis

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Allergy symptoms can range from mild and hardly noticeable to severe and life-threatening. Symptoms of an allergic reaction also vary according to the type of allergy.

Pollen allergy symptoms

Pollen allergy symptoms can emerge immediately if the type of pollen you’re allergic to is in the air. The severity of symptoms may be worse depending on the pollen count in your area. (Pollen count measures how much pollen is in the air.)

Pollen allergy symptoms often include:

• Sneezing
• Stuffy or runny nose
• Red, watery eyes
• Swelling around the eyes
• Itchy nose, ears, eyes, or mouth
• Worsening asthma symptoms

Drug allergy symptoms  

True drug allergies are uncommon. When they occur, symptoms may include: 

• Hives (a skin rash that appears as red or discolored bumps and may be itchy)  
• Swelling of the tongue, lips, or face
• Shortness of breath
• Rash
• Eye or skin itchiness

Drug allergy symptoms typically develop within an hour of taking the drug, though skin rashes may occur several hours, days, or even weeks later.

Insect allergy symptoms  

Insect allergy symptoms usually affect the area around the sting or bite site, although allergic reactions may also extend to other areas of the body. Symptoms can occur minutes to hours after the sting or bite. The most common symptoms of insect allergies include:

• Pain
• Swelling
• Redness or discoloration
• Itching
• Hives
• Worsening asthma symptoms

Food allergy symptoms

Food allergy symptoms can develop within minutes of eating the food you’re allergic to. These symptoms may include:

• Hives
• Itchiness in a certain area or all over the body
• Nausea and vomiting
• Tingling sensations around the mouth
• Swelling of the mouth, throat, or face

Pet allergy symptoms

Pet allergy symptoms tend to occur within 15 minutes of touching a pet, coming into contact with its saliva or urine, or breathing in proteins from its dander. These symptoms may involve:

• Sneezing
• Hives
• Eye redness
• Stuffy or runny nose
• Itchy, swollen eyes or nose
• Itchy, red, or discolored skin
• Postnasal drip (mucus that drains from the nose down the throat, sometimes causing sore throat and cough)
• Worsening asthma symptoms

Mold allergy symptoms  

Mold spores that float in the air can be inhaled through the nose and into the lungs. Symptoms may begin immediately or gradually develop and worsen over time. Some of the most common symptoms of a mold allergy include:

• Sneezing
• Stuffy or runny nose
• Itchy nose, throat, or eyes
• Cough
• Postnasal drip
• Worsening asthma symptoms

Latex allergy symptoms  

Touching or using products made with latex (such as wearing rubber gloves, blowing up a balloon, or putting on a condom) can result in skin irritation and other symptoms. Simply being near latex items, such as birthday balloons or medical gloves, may trigger immediate symptoms in someone with a severe latex allergy.

Common latex allergy symptoms include:

• Itchy, swollen skin
• Sneezing
• Hives
• Red, watery eyes
• Trouble breathing
• Worsening asthma symptoms

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It’s always a good idea to speak with a healthcare provider (HCP) if you develop frequent or worsening allergy symptoms, particularly if they disrupt your daily routine or involve shortness of breath. You should also consult an HCP if over-the-counter (OTC) or prescription allergy medications don’t relieve your symptoms or cause unexpected side effects.

When to call 911 for a severe allergic reaction (anaphylaxis)   

Call 911 immediately if you or someone around you displays symptoms of a severe and life-threatening allergic reaction known as anaphylaxis (or anaphylactic shock). Although rare, insect stings, medicines, latex, and various foods (often nuts and shellfish) can trigger anaphylaxis.

Anaphylaxis symptoms can vary, but may involve:

• Swelling of the tongue or throat
• A sensation of throat tightness
• A sudden drop in blood pressure (shock)
• Trouble breathing or shortness of breath
• Headache
• Dizziness
• Diarrhea, nausea, or vomiting
• Cramps or pain
• Anxiety
• Unusually slow or rapid heart rate
• Loss of consciousness

Someone who is aware that they have a severe allergy will likely be advised to carry an emergency anaphylaxis kit with injectable epinephrine (known as an EpiPen, Auvi-Q, and other names).

Epinephrine is a drug that strengthens heartbeat and opens up the airways. If you carry injectable epinephrine and develop anaphylaxis—or, if someone around you has epinephrine and they’re experiencing signs of anaphylaxis—inject the drug right away according to package directions.

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If you’re one of the millions of people in the U.S. who live with allergies, asking your HCP questions about your condition can help you manage your symptoms and breathe a little easier.

Some basic questions you can ask your HCP about allergies include:

• What do you think I’m allergic to?
• Are my symptoms related to allergies? What are other possible causes of my symptoms?
• Should I take an allergy test? 
• Are my allergies mild, moderate, or severe?
• How can I manage allergies with other conditions I have?
• What are my allergy treatment options? Can you explain the risks and benefits of each?
• How often should I take allergy medication? Every day, or just in response to symptoms?
• Should I see an allergy specialist?
• What allergy symptoms indicate an emergency? When should I call 911 for allergies?

If your HCP suspects you may have allergies, they’ll likely begin by asking you a series of questions, including:

• What your symptoms involve
• How often your symptoms occur
• The severity of your symptoms
• If certain factors cause your symptoms to worsen or improve

Before your appointment, your HCP may ask you to keep a journal or log of your symptoms and what factors (such as certain foods, medicines, or time spent outdoors) seem to trigger them.

Your HCP will also perform a physical exam and ask you questions about your overall health, including what medications or supplements you’re taking or have recently stopped taking.

Depending on your symptoms, your HCP may ask you to stop exposing yourself to possible allergens to see if your symptoms improve. This might involve eliminating certain foods or avoiding the use of certain personal products.

Your HCP may also refer you to an allergist for allergy testing and more specialized care. An allergist is a medical doctor who specializes in allergies and immunology (the branch of medicine that deals with the immune system).

You may be diagnosed with allergies if the pattern of your symptoms, your physical exam, and/or the results of allergy tests suggest that you’re allergic to one or more allergens.

Allergy testing   

Allergy tests can help identify the specific allergens that are triggering your allergy symptoms. Your HCP may recommend one or more types of allergy tests:

Skin allergy testing  

Skin tests for allergies expose an area of skin (usually on the back or forearm) to a very small amount of an allergen to see how the skin responds. If irritation (such as hives, itchiness, or a rash) occurs, you’re likely allergic to the allergen in question.

There are three main types of allergy skin tests: 

• Prick or scratch tests involve pricking or scratching a small drop of an allergen into the surface of the skin. Also known as a percutaneous test, prick or scratch tests are the most common type of allergy test.
• Intradermal tests involve using a very thin needle to inject a tiny amount of an allergen (such as insect venom or penicillin) underneath the skin.
• Patch tests involve placing a small amount of an allergen on the skin, then covering the area with a bandage for 48 to 96 hours.

Usually, an HCP will evaluate several allergens at the same time during a skin allergy test. Signs of a reaction may develop around 15 minutes after the allergen is applied on or injected into the skin.  

Only a qualified HCP should perform a skin allergy test. Although rare, it’s possible for a severe allergic reaction to develop during a skin test. An HCP can provide appropriate medical care if this occurs.

Blood allergy testing  

A blood test for allergies (called ImmunoCAP testing or a radioallergosorbent test) measures the amount of IgE antibodies in the blood. IgE antibodies are produced by the immune system in response to an allergen. The blood sample is sent to a laboratory, where it is evaluated for signs of sensitivities to possible allergens.  

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The first step in managing allergies is avoiding your allergens as much as possible. This may not always be doable, but trying to limit your exposure to allergens like pet dander and latex may reduce your allergy symptoms and help you feel better. Avoiding allergens is particularly important if you’re allergic to a certain food or drug, or if your allergic reactions are severe or have previously involved anaphylaxis.

Most allergy symptoms can be effectively managed with treatment. While allergies aren’t technically curable, treatment can significantly reduce the frequency and severity of allergic reactions. It may take some trial and error, but finding the right treatment plan for your needs can help you live with less disruption from allergy symptoms.

Many people can control their allergy symptoms through a combination of treatment approaches:

Allergy medications  

Several types of allergy medications are available to help ease symptoms and reduce the immune response to certain allergens. Your HCP can help you find the best allergy medicine for your needs. Some of the most widely used types of allergy medication include:

Antihistamines: Prescription and over-the-counter antihistamines help block histamine, which is a chemical released by cells during an allergic reaction. These drugs are available in a variety of forms, including:

• Pills and liquids (such as loratadine, cetirizine, diphenhydramine, and others)
• Nasal sprays (including azelastine and olopatadine)
• Eye drops (such as pheniramine, naphazoline, and ketotifen)

Some antihistamines, including diphenhydramine and chlorpheniramine, cause drowsiness and should be used with caution. Antihistamine nasal sprays may also cause drowsiness or tiredness. Common side effects of antihistamine eye drops include dry eyes and headache.

Decongestants: Decongestants deliver temporary relief from nasal and sinus congestion caused by allergies. Pseudoephedrine, a common, over-the-counter decongestant, is available in pill and liquid form. Several medications combine pseudoephedrine with an antihistamine to treat a wider spectrum of allergy symptoms.

Other nasal decongestants, including oxymetazoline and tetrahydrozoline, are available as nasal sprays and drops.

Carefully follow your HCP’s guidance when using decongestants. Long-term use of these drugs is not recommended, especially for people with high blood pressure, glaucoma, and heart disease. Common side effects of decongestants include headache, elevated blood pressure, and difficulty sleeping.

Corticosteroids: Corticosteroids are anti-inflammatory medications that reduce the immune system’s response to allergens. They’re often used to treat more severe or persistent allergic reactions. There are many types of corticosteroids that are available in several forms, including:

• Pills and liquids (prednisone, prednisolone, and methylprednisolone)
• Nasal sprays (mometasone, triamcinolone, budesonide, and fluticasone)
• Eye drops (prednisolone, flurometholone, and loteprednol)
• Inhalers (mometasone, fluticasone, beclomethasone, ciclesonide, and budesonide) 
• Skin creams (hydrocortisone, mometasone, betamethasone, triamcinolone, and desonide)

The side effects you may experience depend on what type of corticosteroid you’re using and in what form. If you’re taking corticosteroids, be sure to follow your HCP’s guidance and promptly let them know if you develop any unexpected side effects.

Leukotriene inhibitors: Leukotriene inhibitors are prescription medications that help prevent leukotriene chemicals (a type of immune system chemical) from triggering allergies. Available in tablet form, a leukotriene inhibitor called montelukast can relieve runny nose, sneezing, and nasal congestion related to allergic rhinitis (hay fever).

Possible side effects of leukotriene inhibitors include difficulty sleeping, anxiety, depression, or unusual dreams. Contact an HCP immediately if you experience severe anxiety, depression, or thoughts of suicide after taking a leukotriene inhibitor.

Biological medications: Also known as biologics or biologic therapy, biological medications are injections that target certain actions of the immune system that cause allergy symptoms. Examples of biologics for allergies include omalizumab and dupilumab, which treat allergic skin reactions like hives.  

Common side effects of biological medications include itchiness, eye irritation, and irritation around the injection site. 

Allergen immunotherapy 

Allergen immunotherapy may be a viable treatment option if your allergy symptoms can’t be controlled through allergen avoidance and medication alone. This treatment can help reduce allergies by gradually exposing you to increasing amounts of purified allergen extracts over several months or years. The goal of allergen immunotherapy is to build up a tolerance to your allergen, which should result in a significant reduction in symptoms. (Tolerance is the ability to withstand exposure to a substance without adverse effects.)

There are two main types of immunotherapy for allergies:

Allergy shots: Allergy shots contain small doses of an allergen. These injections are usually administered once or twice a week. Depending on the resulting symptoms and your tolerance, the dose may be increased slightly every week or two weeks. Once the maximum tolerated dose is reached, allergy shots are typically administered every two to four weeks.

Possible side effects of allergy shots include allergy symptoms and irritation around the injection site. Rarely, anaphylaxis may occur. Allergy shots generally aren’t used to treat food allergies.

Sublingual immunotherapy: Sublingual immunotherapy (SLIT) involves placing a tablet that contains allergens underneath your tongue until it dissolves. It’s also known as allergy drops.

Over time, SLIT can reduce allergy symptoms like sneezing, runny nose, and eye irritation. SLIT is often used to treat allergies to dust mites and various sources of pollen, including ragweed and several grasses.

Side effects of sublingual immunotherapy may include allergy symptoms or mild itching or swelling around the tongue, lips, or throat. 

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Allergies can cause or contribute to certain health issues, including:   

Anaphylaxis 

Anaphylaxis (anaphylactic shock) is a rare but life-threatening allergic reaction that requires immediate medical treatment. It’s most often linked to food allergies, latex allergies, drug allergies, and insect allergies.   

One in 20 people in the U.S. has experienced anaphylaxis. Every year, anaphylaxis is responsible for around 225 deaths.

Signs of anaphylaxis usually begin within five to 30 minutes of exposure to an allergen, although it’s possible for anaphylaxis symptoms to start more than an hour after exposure. Warning signs of anaphylaxis can vary, but may include:

• Trouble breathing or swallowing 
• A swollen throat 
• Wheezing 
• Loss of consciousness 
• Large rash that can be itchy  

Call 911 immediately if you or someone around you experiences signs of anaphylaxis. Immediate injection with epinephrine—a drug that stimulates a person’s heartbeat—is also necessary.

Many epinephrine shots are administered in the thigh, but this can vary. If you’re at risk of anaphylaxis or have experienced severe allergic reactions in the past, your HCP may advise you to carry an emergency epinephrine shot with you at all times and use it at the first sign of anaphylaxis.

Consider informing your friends, family members, or coworkers about the signs of anaphylaxis and how to inject your prescribed type of epinephrine in the event you’re unable to do so yourself. Wearing a medical alert bracelet that lists your allergies and important medical information may also be a good idea.

Asthma 

Allergies and asthma are closely linked. Many types of asthma (though not all) are worsened by allergies. This is known as allergy-induced asthma or allergic asthma. The same immune responses that trigger allergy symptoms can affect the airways and cause asthma symptoms.

Common signs and symptoms of allergic asthma include:

• Shortness of breath  
• Chest tightness  
• Wheezing 
• Coughing  
• Allergy symptoms like itchy nose and eyes, nasal congestion, and sneezing 

Avoiding allergens to the best of your ability and taking allergy and asthma medications as recommended by your HCP can help you manage allergic asthma symptoms.

Sinus infection  

People who have allergies are more likely to experience inflammation in the nasal passages and sinuses, which can lead to sinus infections (sinusitis). Sinus infections are characterized by inflamed sinuses, which are small, hollow cavities in the skull behind the cheeks, forehead, and nose.  

Sinus infections can linger for several weeks or months. Common signs and symptoms of sinus infections include:

• Nasal congestion with mucus that may appear greenish
• Postnasal drip
• Headache
• Tenderness around the forehead and front of the face
• Pain around the top row of teeth 
• Bad breath
• Fever 

Sinus infection treatment will depend on the cause of the infection. Your HCP may recommend taking an antibiotic, an antihistamine, a decongestant, and a corticosteroid nasal spray to treat the infection and reduce inflammation and congestion in the nasal passages and sinuses.  

Mental health concerns    

For some people, life with allergies can take a mental toll. You may experience anxiety related to the possibility of anaphylaxis or allergic reactions that can feel embarrassing. Allergy symptoms like postnasal drip and nasal congestion may make it hard to sleep at night, which can contribute to various mental health issues. Moreover, excess inflammation plays a major role in both allergies and mental health.

Research supports a link between allergies and mental health issues. One 2019 study published in the International Archives of Allergy and Immunology found that participants with generalized anxiety disorder were more likely to have seasonal allergies to pollen. Those with year-round allergies had a greater chance of depression.

Mental health issues like anxiety and depression can be improved with treatment. Consider speaking with a licensed mental health provider if you’ve been feeling unusually anxious, sad, unmotivated, or hopeless. Joining an in-person or online support group for people with allergies may also be helpful.

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Research suggests that breastfeeding for four to six months after childbirth may help prevent or decrease allergies in a baby. Changing diets during pregnancy or using certain types of formula doesn’t appear to prevent allergies in most children.

Other research indicates that being exposed to certain allergens (such as pet dander and dust mites) in the first year of life may help prevent the development of allergies. Results of some studies suggest that children who are exposed to various allergens at a young age have fewer allergies than children who grow up in more sterile environments. This is known as the “hygiene hypothesis” and is based on the notion that exposure to some allergens and germs can help train and strengthen the immune system.   

A 2023 study published in the Journal of Allergy and Clinical Immunology found that babies who had older siblings (and greater exposure to various allergens) had a more mature gut microbiome at age 1 than babies without older siblings. The gut microbiome is a collection of bacteria that a person has in their digestive system. The more mature and diverse the gut microbiome, the lower the risk of food allergies.

A 2024 study published in the same journal found that young children who attended daycare in their first year of life had significantly lower levels of IgE antibodies and decreased occurrence of food and airborne allergies (such as mold spores and pollen). This may be a result of routine exposure to germs and allergens.

Overall, though, many allergies aren’t preventable. Some people are genetically predisposed to certain allergies. While you may not be able to prevent all allergies, there are some relatively  steps you can take reduce the frequency of allergic reactions.

To help prevent allergic reactions, try to:

Avoid your allergens as much as possible  

For example, don’t play with the neighbor’s dog if you have a pet allergy. If you’re allergic to natural latex, opt for synthetic latex products that won’t trigger allergy symptoms. Consider limiting your time outdoors if the pollen count is high and you have seasonal allergies.

Keep your space clean  

Dust surfaces and vacuum rugs, carpets, fabric couches, and throw pillows regularly. When you dust, use a wet rag to collect more particles. (Dusting with a dry duster or rag merely moves the particles around.)

If possible, use a vacuum with a HEPA filter. You may also want to consider purchasing an air purifier with a HEPA filter to help eliminate airborne allergens. Wash bedding, blankets, and stuffed animals with hot water on a weekly basis. Keeping your home clean can help reduce your exposure to pet dander, dust mites, and pollen that’s drifted in from outside.     

Keep yourself clean  

As exhausted as you may be at the end of a long day, don’t skip that evening shower. Showering at the end of the day rinses off any pollen, pet dander, or other airborne allergens that may have accumulated in your hair or on your skin. The same goes for clothes. When you wash your clothes, don’t forget outerwear like jackets and coats, which can pick up allergens.

Use a dehumidifier  

Mold thrives in damp environments. Using a dehumidifier or a ventilation fan can help prevent mold growth by reducing moisture in areas of your home like the bathroom and kitchen. It’s also important to promptly fix any leaks that may occur in your home and clean up pooled water.  

Eat carefully   

Avoidance is the primary treatment for food allergies. To help prevent food allergy symptoms, it’s important to:

• Read all ingredient labels carefully. This includes checking labels on foods that you wouldn’t think could contain your allergen. Examine all sides of the packaging for messages that include language like “may contain” or “made in a facility with.” Your allergen may not be a primary ingredient, but if an allergen was involved in the manufacturing process, the food could cause an allergic reaction.
• Use caution when eating out. Before eating at a restaurant, inform the manager or chef of your food allergies and ask what can be done to accommodate your needs. Consider skipping dessert, which often contains or comes into contact with common food allergens. 
• Plan ahead when traveling. For instance, you may want to pack your own snacks for the car or plane and bring along extra allergy medication. If you carry emergency epinephrine, keep it with you at all times.
• Educate your child and their teachers. Make sure your child is aware of their food allergens and what snacks to avoid while at school and with friends. Inform teachers of your child’s food allergies and what signs could indicate a medical emergency.

Also check ingredient lists on nonfood items. Some soaps, lotions, medications, and hair care products may contain food ingredients that could cause an allergic reaction.

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Most people with allergies can manage their symptoms with appropriate allergy treatment. Death from allergies is rare, even among people who experience anaphylaxis. While living with allergies can be frustrating or even frightening at times, your HCP can help you identify ways to manage your allergies and breathe a little easier.

Can children outgrow allergies? 

It’s possible for children to outgrow certain allergies. In particular, it’s relatively common for children to outgrow food allergies to eggs, cow’s milk, wheat, and soy. It’s less common for kids to outgrow allergies to fish, shellfish, tree nuts, and peanuts, but it happens. For example, around 20 percent of children outgrow peanut allergies.   

Some (but not all) children may be able to decrease allergies to eggs and cow’s milk by regularly eating baked items with these ingredients. This approach should only be tried under careful medical supervision. Talk to your child’s HCP about how you may be able to safely expose your child to certain allergens.

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Living well with allergies starts with solid allergy management. That may include receiving allergy treatment from your HCP and controlling allergens in your environment to the best of your ability. Doing so can help reduce the frequency and severity of allergic reactions. Your HCP can help you identify strategies to avoid your specific allergens.

To learn more about allergies or to find support, contact your HCP or browse resources from organizations like the Asthma and Allergy Foundation of America.

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• Can Food Additives Cause Allergic Reactions?
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