Insect Allergy

Causes

Stinging insects include:

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

Biting insects include:

• Blackflies
• Fleas
• Horseflies
• Mosquitoes
• Kissing bugs

Insects that cause respiratory allergies include:

• Cockroaches
• Midges
• Lake flies
• Caddis flies

Risk Factors

Factors that increase your chance of insect allergies include:

• Age: young children
• History of other types of allergies, including hay fever
• Family history of allergy
• Occupations that expose you to insects
• Living conditions that expose you to insects or dust-containing insect allergens

Symptoms

An allergy to biting and stinging insects can affect the area around the bite or sting and cause:

• Skin rash
• Hives
• Itching
• Swelling
• Redness
• Hotness

Anaphylaxis can be a life-threatening reaction that causes:

• Skin rash, hives, itching, swelling in areas away from the sting site
• Swelling of lips, tongue, face, throat, and eyelids
• Difficulty breathing, shortness of breath, coughing, wheezing
• Dizziness, fainting
• Severe drop in blood pressure
• Respiratory and/or cardiac arrest

Some insects cause respiratory allergies that result in:

• Runny nose
• Sneezing
• Coughing
• Wheezing
• Difficulty breathing
• Shortness of breath

Diagnosis

The doctor will ask about your symptoms and medical history. A physical exam will be done. Most diagnoses are based on a history of a reaction after a sting. For those with a severe insect allergy, stings may be life-threatening. Therefore, it is important to see an allergist or immunologist (doctor who specializes in allergies).

Tests include:

• Skin prick test—An extract of the insect’s venom or protein is diluted. The dilute is placed on your forearm or back skin. If there is swelling or redness, an allergic reaction may be present. The doctor will make the diagnosis based on the skin test and your history of symptoms. Some skin tests can have a severe allergic reaction. This test should only be used under the supervision of a physician or other trained medical personnel. Severe eczema may make this test hard to interpret.
• RAST or ELISA test—The doctor may order blood tests (RAST or ELISA). These tests measure the level of insect-specific IgE in the blood. IgE is a type of protein that the body produces when it is exposed to something to which it is allergic. The presence of IgE in the blood may indicate an allergy.

Treatment

Some reactions cause trouble breathing. In this case, call for emergency medical help.

Treatment may include:

• Epinephrine—injected immediately in the event of a severe, life-threatening insect sting allergy (anaphylaxis)
• Antihistamine medications—to decrease swelling and itching
• Ice—applied to local area of sting or bite to decrease swelling
• Corticosteroid medications—for more severe swelling, itching, nasal congestion, and sneezing
• Bronchodilators—inhalers that can be used to decrease asthma-like symptoms, such as wheezing, coughing, and shortness of breath
• Venom immunotherapy—a series of allergy shots to gradually desensitize you to insect stings; usually for honeybees, yellow jackets, hornets, wasps, or fire ants

If you are diagnosed with a reaction to an insect bite or sting, follow your doctor’s instructions.

Prevention

To reduce your chance of having an allergic reaction to either biting or stinging insects:

• Avoid stinging insects.
• Be very careful when doing yard or garden work. Beware when hiking in the forest.
• Don’t walk barefoot.
• Don’t wear scented products. Perfumes can attract stinging insects.
• Keep exposed skin to a minimum.
• Consider immunotherapy (allergy shots). These can lessen your reaction to stinging insects
• Carry self-injectable epinephrine and possibly Benadryl for severe reactions.
• Wear a medical alert bracelet or necklace. These will inform others of your allergy.

To reduce your chance of having an allergic reaction to insects that provoke respiratory responses:

• Avoid having carpeting, curtains, or other fabric that may gather dust in your home. This is very important in the room where you sleep.
• Vacuum and wet mop your floors frequently.
• Regularly wash your linens in very hot water.
• Cover mattresses and pillows in allergy-proof covers.