Common Allergy Triggers

Reviewed by Sabrina Felson, MD on October 10, 2019

Your eyes start to itch. You feel a sneeze coming on, out of nowhere.

That’s because your body senses an enemy substance it thinks is going to harm you and gears up for a fight. In other words: You might be allergic to something.

Many things can launch your body into alert mode, from spring pollen to shrimp to tiny mites that live in your bedspread. Allergens -- things you’re allergic to -- can affect your breathing, your skin, your digestive system, and even your senses. Your symptoms will depend on the trigger.

Food Allergies

Eight foods and food groups make up a whopping 90% of serious triggers in the U.S.:

  • Crustacean shellfish, like crab, lobster, and shrimp
  • Eggs
  • Fish
  • Milk
  • Peanuts
  • Soy
  • Tree nuts, like almonds and pecans
  • Wheat

Signs include:

  • Hives. An itchy patch appears on your skin and swells into red welts. It can get worse if you scratch it, drink alcohol, exercise, or get stressed.
  • Lips, tongue, or throat swell
  • Mouth tingles


The most serious allergic reaction is called anaphylaxis. It happens most with food allergies. You might have trouble breathing, and your blood pressure can drop quickly. If this happens, call 911 right away.

What can you do?

  • Avoid foods that cause problems.
  • If you’re at risk for anaphylaxis, your doctor will prescribe a drug called epinephrine in a pen-like gadget called an autoinjector. Even if you use it, you’ll still need to call 911 for further care.
  • See your doctor. They might prescribe antihistamines or a type of steroid to manage nonemergency symptoms.

Drug Allergies

If you have a drug allergy, you can react whether you take a medication as a liquid, pill, or shot.

Antibiotics are a common trigger. Ones to watch for include penicillin and others in the same family, and sulfa drugs.

Other common drug allergy triggers are:

  • Anticonvulsants
  • Aspirin, ibuprofen, and other NSAIDs (nonsteroidal anti-inflammatory drugs)
  • Chemotherapy drugs

Signs to watch for:

  • Hives
  • Itchy skin or rash
  • Swollen face
  • Wheezing (Your breath makes a whistling sound because your airways narrow.)
  • Anaphylaxis

What can you do?

  • Stop taking the meds immediately, and call your doctor.
  • Call 911 if your reaction is severe.

Take antihistamines to ease your symptoms.

Pollen, Mites, and Mold

If you have allergic rhinitis, your body overreacts to something in your environment. It’s also called hay fever. It doesn’t have to refer to hay, or having a fever, though.

It might come with a change in seasons. For example, in the spring and summer, the air is filled with mold spores and pollen from fresh, growing things like grass, trees, and weeds. In some people, ragweed in the fall may trigger allergies.

If you have perennial allergic rhinitis, you have symptoms all year long. Triggers include cockroaches, dust mites, hair or dander from a pet, or indoor mold. Cigarette smoke and perfume fall into this category, too.

Signs to watch for include:

  • Fatigue. This can be from poor sleep because your nose is stopped up.
  • Itchy eyes, nose, or roof of mouth
  • Runny, stuffy nose
  • Sneezing
  • Watery eyes, redness, or swelling

What can you do about it?

  • Ask your doctor about taking meds like decongestants or antihistamines to ease your symptoms.
  • Keep your car and home windows closed during “high pollen” times.
  • Wear a baseball cap outside and wash your hands and face when you get inside.
  • Spring for special bedding that helps keep out mites.
  • Use a dehumidifier to help control mold.

Wash your hands after you’re around animals. If you have pets, find someone else to groom them.

Insect Stings

The venom in an insect sting can spark an allergic reaction. Some people confuse feeling pain from the sting -- which is normal -- for being allergic.


To tell the difference, check your symptoms. If redness and swelling affect a wider area than just the sting site, or if other parts of your body react, your condition is more serious. It needs to be checked out right away.

The main insect sting allergy culprits are:

  • Fire ants
  • Honeybees
  • Hornets
  • Wasps
  • Yellow jackets

Signs of a reaction:

  • Itching or hives all over your body
  • Coughing, wheezing, or shortness of breath
  • Swelling over a large area of the sting site
  • Tightness in your chest
  • Anaphylaxis

What to do

  • Ask your doctor if immunotherapy -- allergy shots -- can help.
  • Stay away from insects.

Inject epinephrine immediately if symptoms happen, then call 911.


Some people are allergic to the proteins in natural rubber latex. It comes from the sap of the rubber tree.


You’ll find it in many places, especially in medical and dental products:

  • Catheters
  • Dental dams
  • Disposable gloves
  • Dressing and bandages
  • Tubing and syringes

Lots of consumer goods contain latex, too, including:

  • Baby bottles, pacifiers, and nipples
  • Balloons
  • Condoms
  • Elastic bands in underwear
  • Rubber toys
  • Tires

Reactions usually happen within minutes of direct contact with a latex item. You also can have a reaction from inhaling the proteins from the powder in latex gloves.

A latex allergy doesn’t apply to synthetic rubber, such as “latex” paint.

What are the signs?

  • Hives and itching
  • Stuffy, runny nose
  • Anaphylaxis

You also can be allergic to chemicals used to make latex rubber gloves. This can cause a rash that looks like poison ivy.

What can you do?

  • Avoid exposure to latex. Many doctors’ offices and hospitals now use non-latex gloves.
  • Wear an allergy alert ID.
  • Carry an epinephrine injector with you. Call 911 if you use it.


WebMD Medical Reference



American Family Physician: “Things That Can Cause Asthma and Allergies.”

Mayo Clinic: “Allergies: Symptoms and Causes,” “Drug allergy: Symptoms,” “Symptoms: Wheezing.”

Food Allergy Research and Education: “About Anaphylaxis,” “Shellfish,” “Symptoms,” “Treatment & Managing Reactions.”

CDC: “Food Allergies in Schools.”

American College of Allergy, Asthma & Immunology: “Types of Allergies: Allergic Rhinitis,” “Types of Allergies: Drug Allergies,” "Types of Allergies: Hives (Urticaria),” “Types of Allergies: Insect Sting Allergy,” “Types of Allergies: Latex Allergy.”

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