Allergic Reactions

What is an allergic reaction?

An allergic reaction is the hypersensitive response of an individual’s immune system to an irritant.

When a normally harmless substance (allergen) enters the body, it can cause the body’s immune system to attack the allergen, creating an adverse (allergic) reaction. Common allergens include:

  • Animal dander
  • Bee/wasp stings
  • Certain medications such as penicillin
  • Dust mites
  • Foods (particularly peanuts, tree nuts, fish, shellfish, eggs, milk, wheat, and soy)
  • Insect bites
  • Latex or other materials you touch
  • Mold
  • Plants and pollen


What are the symptoms of an allergic reaction?

During an allergic reaction, your immune system releases antibodies. These are proteins that deliver a message to cells to attack and remove the foreign substance. The cells then send out histamine, which causes blood vessels to expand, and other chemicals, which trigger the allergy symptoms.

An allergic reaction might range from mild and annoying to severe and even life-threatening.

Anaphylaxis: If your allergy is severe, you may have a serious reaction called Anaphylaxis. It is a serious situation and can eventually lead to shock, which can be life-threatening. Food, medications, insect bites, or latex are frequent causes of anaphylaxis. A second anaphylactic episode can occur up to 12 hours after the first one.

The symptoms of anaphylaxis typically occur suddenly. They can quickly advance from a mild rash, sneezing or runny nose to serious problems such as difficulty breathing, swelling of the lips and tongue, tightness in the throat, and hives or swelling. Some people develop nausea, vomiting, fainting, dizziness, a rapid heart rate, or even irregular life-threatening heart rhythms. Anaphylactic reactions can be life-threatening and need urgent medical attention.

Hay fever:  Hay fever is also known as “allergic rhinitis.” Common symptoms include:

  • Sneezing, runny or stuffy nose
  • Itchy eyes, nose, or roof of mouth
  • Red, swollen watery eyes – a condition known as “allergic conjunctivitis”


Food allergies:

  • You may feel tingling in your mouth.
  • Your tongue, lips, throat, or face might swell up, or you could get hives.
  • In the worst cases, you might have anaphylaxis and will need immediate medical help.


Medication allergies:

  • If you have an allergy to a certain drug, you may get a rash, facial swelling, or hives.
  • You could find yourself wheezing. In severe cases, you may develop anaphylaxis and will need immediate medical help.

Insect bites and stings: 
  • If you are allergic to bees or other insects, you may develop a large area of swelling, known as “edema,” at the site of the sting.
  • The sting may cause itching or hives over your body.
  • Allergic reaction may also include shortness of breath, wheezing, chest tightness, or cough.

As with some other allergies, such as food and medication, a severe reaction to a sting can lead to anaphylaxis, which requires immediate medical help.


How are allergic reactions prevented?

Working with a doctor to create an allergy management plan can help you control the severity and frequency of an allergic reaction. Your strategy depends on your type of allergy. Here are some ways to manage you allergies:

  • Avoid your allergens. This is very important but not always easy. Some allergens are easier to avoid than others. When you cannot avoid an allergen, try to reduce your contact with it.
  • Take your medicines as prescribed. They can be helpful for managing your symptoms. Take them while also avoiding allergens.
  •   If you are at risk for anaphylaxis, keep your epinephrine auto-injectors (EpiPen) with you at all times. Epinephrine is the only treatment for a severe allergic reaction. It is only available through a prescription from your doctor. Most epinephrine prescriptions contain two auto-injectors (pens) in a set.
  • Keep a diary. Track what you do, what you eat, when symptoms occur and what seems to help. This may help you and your doctor find what causes or worsens your symptoms.
  • Wear a medical alert bracelet (or necklace). If you have ever had a severe allergic reaction, please wear a medical alert bracelet. This bracelet lets others know that you have a serious allergy. It can be critical if you have a reaction and you are unable to communicate.
  • Know what to do during an allergic reaction. Have a written anaphylaxis emergency action plan and keep is near you. It tells you and others what to do in case you have allergic symptoms or a severe allergic reaction. Always ask your doctor if you have any questions.


How are allergic reactions treated?

Talk to your doctor about treatment options for allergic reactions. Treatments for mild to moderate allergic reactions may include the following:

  • Antihistamines and decongestants can help treat certain symptoms, as can nasal sprays. Be sure to discuss what over-the-counter (OTC) medicines you are taking with your doctor to avoid negative drug interactions.
  • If you have an allergic-type asthma, your doctor might also prescribe an inhaler to ease attacks.
  • If you do not get enough relief by avoiding your allergens and using medications, you may benefit from allergy shots. This type of treatment is called immunotherapy and it can be effective for hay fever and allergic asthma. Allergy shots are not prescribed at Patient First but your Patient First doctor may refer you to a specialist to determine if they are appropriate for you.

    Your doctor may prescribe medicine that you can give yourself or that someone else can give you. An epinephrine auto-injector, or “EpiPen,” is one type of medicine. If you have had previous attacks of anaphylaxis or know you are at risk for anaphylaxis, follow these guidelines:

    • Carry the injector with you always and be aware of your allergy triggers.
    • Make sure that your family and friends also know how to use the injector in case you are unable to administer it yourself.
    • Call 911 and go straight to an emergency room at the first sign of trouble, even if you have used the injection device. Go even if you are starting to feel better, in case you have a delayed reaction.

    Patient First treats many conditions at our urgent care centers including allergic reactions. You can visit any Patient First center from 8am to 8pm, any day of the week – no appointment is needed