Insect Allergy

Causes

The cause of allergies is unknown. The symptoms are caused by an overreaction of the immune system. Venom from a sting or fluid from a bite may start the reaction.

Common stinging insects linked with allergies are:

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

Common biting insects linked with allergies are:

• Blackflies
• Fleas
• Horseflies
• Mosquitoes
• Kissing bugs

Some insects leave debris in the house that cause reactions. They include:

• Cockroaches
• Midges
• Lake flies
• Caddis flies

These insects can cause reactions all year long. They can also set off asthma.

Risk Factors

Things that raise the risk of insect allergies may be:

• A history of other types of allergies, including hay fever
• Family history of allergy
• Exposure to insects or insect debris from:
  • Work or hobbies
  • Having insects in the home

Symptoms

Symptoms depend on the type of allergy.

A bite or sting can cause:

• Skin rash or hives
• Itching
• Swelling, redness, and warmth

Rarely, stings or bites can cause severe or deadly reactions. The reaction is called anaphylaxis. It can cause:

• Skin rash, hives, itching, and swelling—in places that are not near the sting site
• Swelling of the lips, tongue, face, throat, and eyelids
• Coughing, wheezing, or problems breathing
• Light-headedness, fainting

Insects that live in the house can cause:

• A runny nose or sneezing
• Coughing, wheezing, or problems breathing

Diagnosis

The doctor will ask about symptoms and health history. A physical exam may be done. The doctor may suspect an allergy based on the reaction. An allergy doctor can help.

Tests may include:

• Skin prick test—tiny amounts of an allergen are placed on the skin. The doctor will watch the area for a reaction. If a severe reaction happens, it will be treated right away.
• Blood test—to look at how the body responds to an allergen.

Treatment

Treatment depends on how bad the reaction is. Some reactions cause trouble breathing. They need medical care right away.

General treatment may include:

• Ice—to reduce swelling
• Medicines, such as:
  • Epinephrine injections after a sting—to treat severe reactions
  • Antihistamines—to reduce swelling and itching
  • Corticosteroids—for severe swelling, itching, stuffy nose, and sneezing
  • Inhaled bronchodilators—to reduce wheezing, coughing, and problems breathing

Prevention

Insect allergies cannot be prevented. The risk of a reaction can be reduced by:

• Staying away from stinging insects and things that attract them
• Covering up the skin and feet
• Keeping the home clean and free of insect debris and dust
• Getting allergy shots