What is an allergy attack?
Allergy attacks occur when you come in contact with an allergen (trigger) that your body views as a dangerous invader. Your immune system launches an attack, leading to symptoms such as sneezing, itchy eyes, hives, swelling, and possibly difficulty breathing.
Common allergens include pollen, foods, and medications.
More than 50 million Americans have allergies, and it is the 6th leading cause of chronic illness, according to the American College of Allergy, Asthma, and Immunology.
An allergy attack may be mild and last only a few minutes. For example, you might experience a brief sneezing episode when you clean a dusty room. Or the reaction could be more severe and last for hours or days, such as during hay fever season.
In some cases, you might have severe trouble breathing after eating foods like peanuts. This is called anaphylaxis—it can be deadly if it isn’t treated immediately.
There are a few important things to understand about allergies. Everyone’s allergies are a little different from one another. Allergies are approached differently if you have other medical conditions. Your allergy treatment plan might change over time, too. Your symptoms might get better or worse, or a medication might not work for you anymore or be needed any longer. —Dr. Amrita Khokhar
Main symptoms of an allergy attack
If you’re allergic to airborne allergens, like pollen or dust, you may have sneezing, a runny nose, and red, itchy, and watery eyes. Some people might develop more severe symptoms, like a headache and feeling run down.
When something you ingested, such as a food or medication, triggers an allergy attack, your symptoms may be different—and, in some cases, more severe. Whether you have a mild or severe reaction depends on your individual immune system response. This can make it difficult to predict the intensity of an attack.
If you react to food or medication, you may have hives (a raised, red, and itchy rash) that may develop all over your body. Lip, tongue, or eye swelling may also occur. You might experience wheezing, which develops when your chest gets tight and causes difficulty breathing. You might also experience other symptoms, like an upset stomach or feeling like you might faint. If you begin to experience these symptoms, you might be developing anaphylaxis, which is a life-threatening allergic reaction that requires immediate care in the emergency room.
Common triggers of allergy attacks
Pollen & airborne allergens
- Pollens: Pollen is produced by trees, grasses, and weeds and circulates in the air during spring, summer, and fall.
- Dust: Dust mites are microscopic creatures that live among dust particles and cause dust allergies. They’re most commonly found in carpeting, mattresses, sofas, and any other fabric or upholstered surface that is difficult to wash or clean.
- Animal dander: Cats and dogs are the most common cause of animal allergies. The tiny dead skin cells they shed (dander) is the main culprit. People who spend a lot of time with other animals, like mice or horses, can also develop allergies.
- Mold: Molds can be found indoors in areas with water damage. They’re also commonly found outdoors, especially in moist environments, such as leaf piles or fallen trees.
While food allergies are most common in children, they can also affect adults. Food allergies can lead to anaphylaxis, a severe allergic reaction that affects your whole body and requires emergency treatment. Nine foods cause most allergic reactions:
- Tree nuts
Even if you’ve had a minor reaction to a food—for example, a small bit of lip swelling or just a few hives—it’s very important to see an allergist, get allergy testing, and talk about a plan of care. Small reactions can suddenly turn into big reactions the next time you’re exposed. —Dr. Khokhar
While any medication can cause an allergic reaction, there are a few types that are more likely to do so. For example, antibiotics such as penicillin or those that contain a compound called “sulfa” are the most common causes of medication allergies. Over-the-counter pain medications like non-steroidal anti-inflammatory drugs (NSAIDs) are also frequent triggers of allergic reactions. Other medications that are known to cause allergic reactions include chemotherapy drugs and seizure medications.
Stings from bees, wasps, yellow jackets, and hornets all contain venom that can lead to an allergic reaction. Sometimes your symptoms may be mild (such as swelling at the site of the sting), but in some cases the sting can cause anaphylaxis.
How to stop an allergy attack
If you have allergies to pollens, dust, or other allergens that float in the air, there are a few steps you can take to stop your reaction.
- Remove yourself from the area. If you’re outdoors and having a reaction to pollen, go inside. Change your clothes and take a shower to remove the pollen from your body.
- Try an antihistamine. An antihistamine is an allergy pill that can help treat symptoms like sneezing and itchy, watery eyes. These are available over the counter and can be taken when needed, or even every day if you’re having daily symptoms.
- Use nasal saline rinses. Nasal saline can help flush out pollen and other airborne allergens from your nose. They’re available over the counter in the form of squeeze bottles, nasal teapots (neti pots), or sprays.
If you’re having a severe allergic reaction (anaphylaxis), emergency medication and treatment is required. You might be having a severe allergic reaction if you begin to develop swelling of your tongue or throat, you develop hives all over your body, you have difficulty breathing or your chest feels tight, or you feel lightheaded and faint.
If you’ve already been diagnosed with severe allergies, your doctor will have prescribed you injectable epinephrine, also called an “EpiPen.” If you ever start experiencing symptoms of anaphylaxis, use the Epipen and call 911 right away.
If you’ve been diagnosed with a food or venom allergy (like bees or wasps), you should carry an EpiPen. You will be specifically instructed by your allergist about how and when you should use your EpiPen in the form of a written “action plan.” —Dr. Khokhar
Why allergic reactions happen
Allergic reactions happen when your immune system overreacts to an otherwise harmless substance. But what actually happens in your body when you develop an allergy?
The first time you’re exposed to an allergen, like cat dander, it’s likely you won’t have any issues at all. This is because your immune system takes some time to “study” the allergen before reacting to it.
Over time, the immune system begins to produce “antibodies,” which are a form of defense against the specific allergen. When you’re exposed to cat dander after these antibodies are created, your body sees the dander as an invader. The antibodies then activate cells in the body that release chemicals, like histamine, which cause the symptoms.
How to avoid an allergy attack
If you think you have allergies, an allergy test can help make the diagnosis. Allergy tests are available for environmental allergens, foods, insect venoms, and some medications, too.
Allergy testing, called “skin prick” or “scratch” testing, is performed on the skin, usually on your arms or back. Your doctor will place a small amount of the allergen in question on your skin and then poke the area with a tool such as a needle or lancet to allow the allergen to penetrate the surface of your skin. After 15 minutes, your doctor will check to see if you’ve developed any swelling or redness in the area.
In some cases, blood testing can also be used to check for allergies.
Allergy testing is especially important if you have food allergies. Identifying and avoiding the food you’re allergic to is the most important step in preventing allergic reactions.
Reduce your exposure to airborne allergens
Check your local pollen count: Avoid going outdoors very early in the morning, which is when pollen levels tend to be at their peak. Keep your windows closed to avoid letting pollen into your house and car (use air conditioning instead whenever possible). If you’ve been outside for a while, get pollen out of your hair and off of your skin by changing your clothes and taking a shower when you go inside.
Animal dander: Avoiding the animal you’re allergic to is the best way to prevent a reaction. But if you live with a dog or a cat and you’re allergic, there are a few steps you can take to reduce your exposure. Don’t allow the pet into your bedroom or onto your upholstered furniture. Vacuum frequently and try using a HEPA air purifier to trap airborne dander, especially if you have cats.
Dust: Remove carpeting, which is one of the main areas where dust is found in homes. Covering pillows and mattresses with dust mite covers can help, too. Dust mites thrive in humid places, so try to keep humidity levels low in your home.
Medications and immunotherapy
There are many medications you can use to prevent an allergy attack. Some are over the counter, such as antihistamines or nasal steroid sprays. However, your doctor may recommend prescription medications if over-the-counter remedies aren’t working or you can’t tolerate them.
Allergy immunotherapy—commonly referred to as allergy shots—is another option. You’ll get regular shots, gradually increasing the dosage of the allergen. This trains your immune system to become less sensitive to it. You can also take dissolvable oral tablets to treat very specific types of allergies, like dust or ragweed (a type of weed pollen).
For food allergies, some promising treatments are on the horizon, such as oral immunotherapy (OIT). In OIT, you eat tiny but gradually increasing amounts of the food you’re allergic to. Over time, this can help protect you from developing a severe allergic reaction if you accidentally eat a large amount of that food.
While most OIT treatments have been offered as part of clinical studies, the Food and Drug Administration approved the first OIT, called Palforzia, for peanut allergies in 2020.