Allergies Caused by Insect Stings can be alarming By Dr. Joann Lin McKinney Allergy and Asthma

Summer is upon us and it’s time to watch out for all the creepycrawly, flying insects that love the heat as much as people do! Most insect stings are an itchy nuisance, but, for some, a bite
or sting can be much more alarming and lead to severe, lifethreatening allergic reactions.

How to treat an insect sting
Most people will develop itching, pain, swelling, and redness confined to the sting/bite site. With fireant stings, the itchy bump later develops into a small blister. There is little chance of infection unless it is scratched opened. When healed, these lesions may leave scars.

For insect sting treatment, disinfecting the area (washing with soap and water) and applying ice will help to reduce the swelling. Antihistamines can help control itching and reduce the
chance of infection developing when the skin is scratched open. Some people may develop significantly larger reactions where an entire arm or leg will swell. Medical attention may
be required if the swelling causes significant pain or does not subside. Antihistamines and corticosteroids may be prescribed to lessen the discomfort.

What are the symptoms of insect sting allergy?
People with true insect sting allergies develop severe, lifethreatening symptoms after insect stings because their immune system overreacts to the venom. About 0.5-5% of the US
population develop these symptoms after insect stings. These severe allergic, or anaphylactic, symptoms include:

• Hives, itching and swelling in areas other than the sting site
  
• Tightness in the chest and difficulty in breathing
  
• Hoarseness or tongue swelling
  
• Dizziness and fainting
  
• Stomach cramping
• Nausea and/or diarrhea

Most allergic reactions to insect stings in the US come from wasps, yellow jackets, hornets, bees, and fireants. Mosquito bites very rarely lead to anaphylaxis.

How are allergic reactions to insect stings treated?
Life-threatening allergic reactions can progress very rapidly within minutes and require immediate medical attention. Emergency treatment usually includes medications like epinephrine, antihistamines, and in some cases, corticosteroids, intravenous fluids, and breathing treatments.

Avoiding insect stings
Knowing how to avoid stings leads to a more enjoyable outdoor experience. Stinging insects are most active during the summer and early fall. Some interventions include:

• Avoid wearing sandals or walking barefoot in the grass.
  Honeybees and bumblebees forage on white clover, a weed that grows in lawns throughout the country
  
• Never swat at a flying insect. If need be, gently brush it aside
• Be careful when you drink from open beverage cans. Stinging insects can crawl into an open can
  
• When eating outdoors, try to keep food covered at all times
  
• Garbage cans stored outside should be covered with tightfitting lids
  
• Avoid sweet-smelling perfumes, hair sprays, colognes and deodorants
  
• Avoid wearing bright-colored clothing
  
• Wear appropriate covering to minimize skin exposure during yardwork and gardening
  
• Keep window and door screens in good repair. Drive with car windows closed
  
• Keep prescribed medications handy at all times and follow the attached instructions if you are stung
  
• Insect repellants are more effective against mosquitoes and tics. Those containing DEET should not be used in children under 2 months of age. Oil of eucalyptus products should not be used in children under 3 years old. When applying insect repellant, apply to only exposed skin but avoid their hands, around the eyes, or any areas where there are cuts or irritated skin. When using combination products with DEET and sunscreen, you may reapply sunscreen but the combination product should not be reapplied because repeated application may increase the potential
  toxic effects of DEET
  
• Fireants, yellow jackets, hornets and wasps can sting repeatedly. Honeybees have barbed stingers that are left behind in their victim's skin. These stingers are best removed by a scraping action with your fingernail, rather than a pulling motion which may actually squeeze more venom into the skin.

Diagnosis and treatment of severe insect sting allergy
An allergist can help you diagnose insect sting allergy through blood testing or in-office skin testing. If the test is positive, your doctor will prescribe you a portable self-injectable epinephrine device for emergency use if you have a severe reaction. People who have experienced an allergic reaction to an insect sting have a 60% chance of a similar or worse reaction if stung again. Long-term treatment is through venom immunotherapy, a highly
effective program of allergy shots which can prevent future severe allergic reactions to insect stings. In a matter of weeks to months, people who previously lived under the constant threat of severe reactions to insect stings can return to leading normal lives outside! Being prepared for insects and taking certain precautions will help everyone enjoy multiple outdoor activities this season!

Joann H. Lin, MD
McKinney Allergy and Asthma Center
972-548-2797