SATURDAY, June 11 (HealthDay News) — For most people, insect stings are a painful annoyance, but they can be deadly for those who are allergic to them, researchers warn.

Each year in the United States, more than half a million people have to go to emergency departments after suffering insect stings, and at least 50 die, according to the American College of Allergy, Asthma and Immunology, which recently released updated guidelines for diagnosing and treating people with hypersensitivity to insect stings.

Its three key recommendations for people who are allergic to stings:

  • Consider allergy shots
  • Avoid all stinging insects, including bumblebees
  • Be aware of factors that increase the chances of a serious reaction

Research indicates that allergy shots are effective in preventing allergic reactions to stings. The shots work like a vaccine, exposing recipients to increasing amounts of the stinging insect allergen in order to boost the immune system’s tolerance of it.

And although bumblebees are considered less aggressive than hornets and wasps, a growing number of severe allergic reactions are being caused by bumblebees, particularly among greenhouse workers. Because of this, people should try to avoid bumblebees as much as other stinging insects, the group advises.

In addition, the allergy experts noted, certain people are at increased risk for serious allergic reactions to insect stings. Factors associated with a higher risk include: a history of severe or near-fatal reactions to insect stings; heart disease, high blood pressure or pulmonary disease in those who have had a reaction beyond the site of a sting; asthma; taking certain medications, including beta blockers or ACE inhibitors; and frequent exposure to stinging insects, such as among gardeners and beekeepers.

Symptoms of a severe allergic reaction to stings include:

  • Hives, itching and swelling in areas other than the sting site
  • Tightness in the chest and difficulty breathing
  • Swelling of the nose, lips, tongue and throat
  • Dizziness, fainting or loss of consciousness

Medical experts stress that anyone who has any of these symptoms should seek immediate medical attention at the nearest emergency department.

More information

The U.S. Food and Drug Administration has more about bug bites and stings.