Insect bites and stings can cause an immediate skin reaction. The bite from fire ants and the sting from bees, wasps, and hornets are usually painful. Bites caused by mosquitoes, fleas, and mites are more likely to cause itching than pain.

In most cases, bites and stings can be easily treated at home. However, some people have a severe allergic reaction to insect bites and stings. This is a life-threatening allergic reaction known as anaphylaxis, and it requires urgent emergency care. Severe reactions can affect the whole body and may occur very quickly, often within minutes. These severe reactions can be rapidly fatal if untreated. Call 911 if you are with someone who has trouble breathing or goes into shock.

Some spider bites, like those of the black widow or brown recluse, are also serious and can be life-threatening. Most spider bites, however, are harmless. If bitten by an insect or spider, bring it for identification if this can be done quickly and safely.

The non-emergency symptoms vary according to the type of insect and the individual. Most people have localized pain, redness, swelling, or itching. You may also feel burning, numbness, or tingling.

For emergencies (severe reactions):

1. Check the person's airways and breathing. If necessary, call 911 and begin rescue breathing and CPR.
2. Reassure the person. Try to keep him or her calm.
3. Remove nearby rings and constricting items because the affected area may swell.
4. Use the person's Epi-pen or other emergency kit, if they have one. (Some people who have serious insect reactions carry it with them.)
5. If appropriate, treat the person for signs of shock. Remain with the person until medical help arrives.

General steps for most bites and stings:

1. Remove the stinger if still present by scraping the back of a credit card or other straight-edged object across the stinger. Do not use tweezers -- these may squeeze the venom sac and increase the amount of venom released.
2. Wash the site thoroughly with soap and water.
3. Place ice (wrapped in a washcloth) on the site of the sting for 10 minutes and then off for 10 minutes. Repeat this process.
4. If necessary, take an antihistamine, or apply creams that reduce itching.
5. Over the next several days, watch for signs of infection (such as increasing redness, swelling, or pain).

• Do NOT apply a tourniquet.
• Do NOT give the person stimulants, aspirin, or other pain medication unless prescribed by the doctor.

Call 911 if the person is having a severe reaction:

• Trouble breathing, wheezing, shortness of breath
• Swelling anywhere on the face
• Throat feels tight
• Feeling weak
• Turning blue

• Avoid provoking insects whenever possible.
• Avoid rapid, jerky movements around insect hives or nests.
• Avoid perfumes and floral-patterned or dark clothing.
• Use appropriate insect repellants and protective clothing.
• Use caution when eating outdoors, especially with sweetened beverages or in areas around garbage cans, which often attract bees.
• For those who have a serious allergy to insect bites or stings, carry an emergency epinephrine kit (which requires a prescription). Friends and family should be taught how to use it if you have a reaction. Wear a medical ID bracelet.

Goldman L, Ausiello D, eds. Cecil Textbook of Medicine, 22nd ed. Philadelphia, Pa: Saunders; 2004.

Noble J, Greene HL, Levinsen W, eds. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001.

Auerbach PS, ed. Wilderness Medicine. 4th ed. St. Louis, Mo: Mosby; 2001.