Nearly 50 million people in the U.S. suffer from an allergic disease, according to the American Academy of Allergy, Asthma & Immunology (AAAAI). While the immune system is useful in defending the body against viruses and bacteria, the immune system may defend itself against substances that shouldn’t pose a threat to humans. These substances are referred to as allergens and your body’s defense is an allergic reaction.
What Causes an Allergic Reaction?
Why some people experience allergies is a mystery. Allergies may run in families and can be inherited. If a member of your family has allergies, you may be more likely to develop allergies.
The cause of the reaction can be traced to common substances. People with allergies are typically allergic to:
- Bee stings (or other insect bites)
- Foods (nuts, shellfish, etc.)
- Medications (aspirin, penicillin, etc.)
- Pet dander
What Are Common Symptoms of an Allergic Reaction?
Depending on the substance you are allergic to, symptoms can affect your skin, digestive system, airways, sinuses, and nasal passages. These reactions can range from mild to severe and can trigger anaphylaxis, a life-threatening reaction.
Mild allergic reaction symptoms
- Nasal congestion
- Scratchy throat
- Watery eyes
Severe allergic reaction symptoms
Severe reactions can cause anaphylaxis, a life-threatening reaction, resulting in a sudden drop in blood pressure, swelling of the airway, and difficulty breathing. If you experience a severe reaction, seek emergency assistance right away.
Additional severe symptoms include:
- Flushing of the face
- Difficulty breathing
- Difficulty swallowing
- Heart palpitations
- Nausea or vomiting
- Pain or tightness in chest
- Swelling of face, eyes, or tongue
How Are Allergies Diagnosed?
Your doctor or allergist can diagnose if you are allergic to foods or other environmental substances through exams and asking about your health history. Your doctor may perform one of the following three tests to determine your allergy.
Allergy Skin Testing
With an allergy skin test, your allergist will apply a trace of a suspected allergen on your skin and wait for a reaction. The substance may be applied by a small prick to the skin, injected under the skin, or taped to the surface of the skin. If you are allergic to one of the tests, you may experience redness and swelling at the test spot within 20 minutes. Delayed reactions may take several hours and typically disappear within 24 to 48 hours.
Skin tests are useful in diagnosing food and environmental allergens, including:
- Allergic contact dermatitis (rash)
- Bee sting or insect allergy
- Food allergy
- Penicillin allergy
- Mold, pollen, or pet dander allergy
Allergy Elimination (or Challenge) Testing
To find out if you are allergic to a certain food, your doctor may suggest removing the food from your diet for several weeks. As you add the food back into your diet, you will be instructed to watch if any symptoms occur.
Allergy Blood Tests
If skin tests are not possible, your allergist may suggest a blood test to look for substances in the blood called antibodies. The most common test measures the blood level of an antibody, immunoglobulin E (IgE), which the body may make in response to an allergen. IgE levels are often higher in people with asthma or allergies.
7 Tips for Controlling an Allergic Reaction
Most people don’t know they have an allergy until symptoms occur. If you experience symptoms of an allergic reaction, here’s how you can help control them:
- If a severe reaction causes anaphylaxis, seek emergency medical help immediately. An epinephrine auto-injector (adrenaline) may be needed to manage the reaction right away.
- If an allergen causes a skin reaction such as a rash, wash the area thoroughly with mild soap and apply topical creams or medications to control the itching.
- Seasonal allergies can be treated with antihistamines and decongestants to reduce symptoms. Talk to your allergist about allergy shots to reduces reactions to seasonal allergies over time.
- Food allergy symptoms such as hives or itching can be treated with over-the-counter drugs. Prescription drugs are needed to treat other symptoms. Severe food allergies may be treated with epinephrine.
- Plant allergies causing redness, itching, swelling, and blisters can spread by touch. Thoroughly cleanse the area with soap and water for 10 minutes and take a cool bath. Apply anti-itching (calamine) lotion three to four times a day. See your doctor if symptoms get worse.
- If you experience an insect string, carefully removing the stinger in a swiping motion and wash the area with soap, water, and apply an antiseptic. Apply calamine lotion or hydrocortisone cream and cover the area with a bandage. An antihistamine can reduce itching, swelling, and hives.
- Drug allergies can be treated with an alternative prescription provided by your doctor. Epinephrine, antihistamines, and corticosteroids may be needed for serious drug allergy reactions.
See an Allergist for Diagnosis and Treatment
Allergies can develop at any age. If you experience symptoms of a severe allergic reaction, seek emergency medical help immediately. Schedule an appointment with an allergist to determine the cause(s) of an allergic reaction and to create a treatment plan.
Need help with your allergies? Contact the Allergy & Asthma Specialists of North Florida for diagnosis and treatment of allergies.