How to Identify Allergies

Having an allergic reaction can be scary, especially if you don't know what's causing it. We're here to answer some of your most commonly-asked questions about allergies, including what the symptoms are and what might be causing them. To be 100% sure what's going on, though, make an appointment with an allergist for allergy testing. However, if you're having symptoms of a severe allergic reaction, like you're having trouble breathing, get emergency medical help as soon as possible.

[Edit]Steps

[Edit]What are the symptoms of an allergic reaction?

1. Allergies can present with a lot of different symptoms. This mostly depends on what type of allergic reaction you're having, although similar allergies can present differently for different people. There are a few common, symptoms, though. These might include:
   
   • An itchy or tingling feeling in your mouth^[1]
   • Itchy, red, or watery eyes^[2]
   • Sneezing or an itchy, runny, or stuffy nose
   • Wheezing, trouble breathing, coughing, or tightness in your chest
   • Itchy skin, raised welts (called hives), or eczema
   • Swelling in your lips, tongue, face, eyes, or throat
   • Stomach pain, nausea, vomiting, or diarrhea
2. Get emergency help if you have symptoms of a severe allergic reaction. Sometimes, an allergy can lead to a severe reaction called anaphylaxis. If this happens, you need to get emergency medical care right away, or it could lead to coma or even death. If you've already been prescribed an epinephrine injection, give it to yourself as quickly as possible, but still get to the emergency room in case the symptoms return.^[3] Symptoms of anaphylaxis include:^[4]
   • A swollen throat or constriction of your airways
   • The feeling of a lump in your throat
   • Shock
   • Sudden drastic drop in blood pressure
   • Rapid pulse
   • Dizziness or fainting

[Edit]How do you know if you have allergies or a cold?

1. You can usually tell by checking your mucus, cough, and temperature. Ok, this doesn't sound like much fun, that's true. However, these things can give you some big clues as to whether you're experiencing allergies or if you might have a cold or another illness. Specifically, check these things:^[5]
   
   • The color of your mucus: If you have allergies, it should stay clear. If you have a cold, it will get thicker, cloudy, and yellow.
   • Type of cough: If you have a nagging, dry cough, chances are, it's just allergies. On the other hand, if you're coughing up mucus, it's likely a cold, although it could also be a virus like the flu or COVID-19.
   • Sore throat: If you're sick with something like a cold or the flu, you'll often get a sore throat, but that's uncommon with allergies.
   • Fever: Severe allergies can sometimes lead to a fever, but it's pretty rare, and you'll likely have other severe allergy symptoms. Fever is much more common with illnesses like a cold or the flu.

[Edit]How do you know what you're allergic to?

1. Track your symptoms at home to narrow down your triggers. Every time you experience allergy symptoms, write them down in a notebook or an app on your phone. Note anything you ate or drank, whether you touched any animals, any lotions, soaps, or cosmetics you used, and anything else you can think of that might be relevant. You might even write down what you were wearing—you could be allergic to a certain fabric or laundry detergent.^[6]
   
   • In addition, write down where you were—like whether you were indoors or outdoors.
   • Try to think back for at least a couple of hours before your symptoms occurred. Allergies symptoms usually show up pretty quickly after exposure to your allergen, but they can sometimes take a while to develop.^[7]
2. See an allergist for testing to know for sure. Although it's fine to discuss your allergy concerns with your primary care provider, it's best to see an allergist for further testing and treatment. At your first appointment, go over your allergy diary with your allergist. They'll also likely talk to you about your family history, and they may do a physical exam.^[8]
   • Your allergist will likely recommend testing to determine exactly what's triggering your allergies. A skin prick test is the most common type of allergy test, although they may suggest other tests, as well.

[Edit]What does an allergy test consist of?

1. Skin prick tests are the most common type of allergy test. During this test, a drop of an allergen will be placed on your skin (usually your arm or back), then the allergist will prick your skin gently. They'll usually test several different substances at once. If the location of the prick turns red, you're likely allergic to that substance. This can be a little uncomfortable, but don't worry—it's not painful.^[9]
   
   • If the results of your skin prick test aren't clear, the allergist might do a second test where the allergens are injected under the first few layers of your skin. This is called an intradermal test.^[10]
   • They might also draw blood for a lab test if a skin test isn't a good option, like if you have very sensitive skin, you've had a severe allergic reaction in the past, or you take a medication that would affect the test results.^[11]

[Edit]What are the most common types of allergies?

1. There are four major types of allergies. Typically, people are allergic to something in their environment, food, insect stings, or medications. You may be allergic to one or more items within these categories, as well.
   
   • Environmental allergies can include seasonal allergies to pollen, perennial allergies to things like mold and pet dander, and contact allergies that lead to skin irritation.^[12]
   • Food allergies can occur when you eat a certain food, although if they're severe, they might be triggered when you simply touch or breathe in that item.
   • Insect allergies typically only occur when you are bitten or stung by the insect you're allergic to.
   • Medication allergies can occur with both prescription and over-the-counter drugs, but they are not the same as side effects from taking medication.^[13]

[Edit]What is allergic rhinitis?

1. Allergic rhinitis is the sneezing, sniffling type of allergies. If you have allergic rhinitis, it might only show up during certain seasons, although it can also occur year-round, depending on your trigger. Typical symptoms include sneezing, a runny or stuffy nose, and itchy, watery, or swollen eyes.^[14]
   
   • If your allergies tend to occur in the spring or fall, you likely have seasonal allergies, or hay fever. This is triggered by pollen in the air.
   • If your allergies last all year, you might be allergic to something like animal dander, dust mites, mold, or debris left by cockroaches.^[15]

[Edit]What are contact allergies?

1. Contact allergies are skin-related. If your skin is itchy, red, or flaky, there's a chance that something you're touching is causing an allergic reaction. Some people are sensitive to the chemicals in laundry detergent and fabric softener, so if you've recently changed brands (or your favorite brand has changed their formula), that's a good place to start. Other skin-related allergens might include:^[16]
   
   • Cosmetics, soaps, or lotions
   • Certain fabrics or dyes
   • Latex or rubber
   • Topical medications
   • Irritants like poison oak or sumac
   • Nickel or other metals

[Edit]How can you tell if you have a food allergy?

1. Your symptoms will appear shortly after you eat your trigger food. You might have tingling in your mouth; swelling of your lips, tongue, face, or throat; hives; or an anaphylactic reaction after you eat. Since allergies can be triggered by a hidden ingredient in your food, it's important to see an allergist to determine exactly what you need to avoid. Common foods that trigger allergies include:^[17]
   
   • Shellfish (shrimp, lobster, crab)
   • Fish
   • Peanuts or tree nuts (pecans, walnuts)
   • Cow's milk
   • Eggs
   • Soy
   • Wheat
   • Certain raw foods
2. Try an elimination diet if your allergist suspects food allergies. This involves cutting any foods completely out of your diet that you might be allergic to for about 1-2 weeks. Then, you'll introduce them back in one at a time, waiting a few days each time to see if you have any reaction to them.^[18]
   • This won't always give you precise results—an elimination diet can't tell you if you're sensitive to a food as opposed to being truly allergic to it, for instance.^[19]
   • Only do an elimination diet under the guidance of an allergist. If you've ever had a severe food reaction, it's probably not safe to do an elimination diet at all.
   • Your allergist might also recommend an oral food challenge, where you'll eat small amounts of a trigger food to see if you have a reaction. Because you could have a life-threatening allergic reaction, this should only ever be done in your allergist's office or a hospital setting, and only under direct medical supervision.^[20]

[Edit]Can you be allergic to insect bites?

1. Yes, some people are allergic to things like bee or wasp stings. This can occur even if you aren't allergic to anything else, and the reactions can sometimes be pretty severe. Typically, you'll notice a quick reaction when you're bitten or stung, and there will likely be significant swelling at the site of the sting. Other symptoms might include:^[21]
   
   • Itching or hives
   • Tightness of the chest
   • Wheezing
   • Cough
   • Trouble breathing
   • Anaphylaxis

[Edit]Can people be allergic to medicine?

1. Yes, talk to your doctor right away if you think this is the case. Although it's important to take all of your medication as directed by your healthcare provider, if you think you're having an allergic reaction to something you've taken, stop using it right away and call the doctor. They'll work with you to determine if that's the cause of your symptoms, and if so, what else you might take instead. Some of the symptoms of a medication allergy might include:^[22]
   
   • Hives, itching, or a rash
   • Swelling of your face
   • Wheezing or shortness of breath
   • Anaphylaxis
2. Certain medications and conditions may make allergies more likely. You might be more likely to experience a drug allergy if you take medications like penicillin, certain pain relievers, chemotherapy drugs, or medicines that treat autoimmune diseases. Other things that might increase your risk include:^[23]
   • Having other allergies, like hay fever
   • Taking the drug for a long time or at high doses
   • Having certain illnesses like HIV
   • Having a history or family history of allergies to other medicines.

[Edit]Tips

• Allergies can be short-lived or they might linger for weeks or months, depending on what's triggering them and how you're being exposed to that substance.^[24]
• A food intolerance isn't the same as a food allergy, although they may have some of the same signs. See a doctor to determine which you're experiencing.^[25]
• If you do have allergies, work with your allergist to develop a treatment plan.^[26]

[Edit]Warnings

• If you experience any signs of an allergic reaction, see your doctor. If the reaction is severe, get emergency medical assistance right away.

[Edit]Related wikiHows

• Treat Allergies
• Deal With Being Allergic to Cats
• Recognize an Allergic Reaction

[Edit]References

1. ↑ https://www.mayoclinic.org/diseases-conditions/food-allergy/symptoms-causes/syc-20355095
2. ↑ https://www.nhs.uk/conditions/allergies/symptoms/
3. ↑ [v161496_b01]. 29 July 2020.
4. ↑ https://www.mayoclinic.org/diseases-conditions/allergies/symptoms-causes/syc-20351497
5. ↑ https://www.health.com/condition/allergy/allergies-or-cold
6. ↑ https://www.allergy.org.au/patients/allergy-testing/causes-of-allergy
7. ↑ https://www.nhs.uk/conditions/allergies/symptoms/
8. ↑ https://acaai.org/allergies/allergy-treatment/diagnosing-allergies
9. ↑ https://www.nhs.uk/conditions/allergies/diagnosis/
10. ↑ https://acaai.org/allergies/allergy-treatment/diagnosing-allergies
11. ↑ https://acaai.org/allergies/allergy-treatment/diagnosing-allergies
12. ↑ https://community.aafa.org/blog/sneezing-and-sniffling-how-to-tell-if-its-allergies-or-a-cold-and-warning-for-people-with-asthma
13. ↑ https://www.mayoclinic.org/diseases-conditions/drug-allergy/symptoms-causes/syc-20371835
14. ↑ https://www.mayoclinic.org/diseases-conditions/allergies/symptoms-causes/syc-20351497
15. ↑ https://community.aafa.org/blog/sneezing-and-sniffling-how-to-tell-if-its-allergies-or-a-cold-and-warning-for-people-with-asthma
16. ↑ https://medlineplus.gov/ency/article/000869.htm
17. ↑ https://www.mayoclinic.org/diseases-conditions/food-allergy/symptoms-causes/syc-20355095
18. ↑ https://www.foodallergy.org/resources/food-elimination-diet
19. ↑ https://www.mayoclinic.org/diseases-conditions/food-allergy/diagnosis-treatment/drc-20355101
20. ↑ https://kidshealth.org/en/parents/food-allergies.html
21. ↑ https://www.mayoclinic.org/diseases-conditions/allergies/symptoms-causes/syc-20351497
22. ↑ https://www.mayoclinic.org/diseases-conditions/allergies/symptoms-causes/syc-20351497
23. ↑ https://www.mayoclinic.org/diseases-conditions/drug-allergy/symptoms-causes/syc-20371835
24. ↑ https://acaai.org/allergies/allergy-treatment/diagnosing-allergies
25. ↑ https://www.mayoclinic.org/diseases-conditions/food-allergy/symptoms-causes/syc-20355095
26. ↑ https://kidshealth.org/en/parents/food-allergies.html