Overview

Insect and spider bites often cause minor swelling, redness, pain, and itching. These mild reactions are common. They may last from a few hours to a few days. Home treatment is often all that's needed to relieve the symptoms of a mild reaction to common stinging or biting spiders and insects, such as fleas, flies, and mosquitoes.

Some people have more severe reactions to bites or stings. Babies and children may be more affected than adults are.

Examples of problems that are more serious include:

• A severe allergic reaction (anaphylaxis). These reactions aren't common. But they can be life-threatening and require emergency care. They may cause:
  • Shock. This can occur if the circulatory system can't get enough blood to the vital organs.
  • Coughing, wheezing, trouble breathing, or a feeling of fullness in the mouth or throat.
  • Swelling of the lips, tongue, ears, eyelids, palms of the hands, soles of the feet, and mucous membranes (angioedema).
  • Light-headedness and confusion.
  • Nausea, diarrhea, and stomach cramps.
  • Raised, red, itchy bumps called hives and red skin. These symptoms often occur with other symptoms of a severe reaction.
• A toxic reaction to a single sting or bite. Spiders or insects that may cause this include:
  • Black widow spiders.
  • Brown recluse spiders.
  • Scorpions.
  • Puss caterpillars (woolly slugs).
• A toxic reaction to multiple stings or bites from a bee, wasp, or fire ant.
  • A bee leaves its stinger behind and then dies after stinging. Africanized honeybees, the so-called killer bees, are more aggressive than common honeybees. They often attack together in great numbers. Reaction to bee stings can range from minor skin swelling and redness to a serious allergic reaction.
  • Wasps, including hornets and yellow jackets, can sting over and over.
  • A fire ant is a wingless insect. It attaches to a person by biting with its jaws. Then, pivoting its head, it stings from its belly in a circular pattern at multiple sites.
• A large skin reaction with swelling and redness that spreads away from the site of the bite or sting. It may be as large as swelling across two major joints, such as from the elbow to the shoulder.
• A skin infection at the site of the bite or sting.
• 
  Serum sickness. This is a reaction to the medicines (antiserum) used to treat a bite or sting. It may cause hives and influenza (flu) symptoms, such as a fever, muscle aches, or a headache about 3 to 21 days after the use of antiserum.
• A virus infection. Infected mosquitoes can spread the West Nile virus to people, causing an inflammation of the brain (encephalitis).
• A parasite infection. Infected mosquitoes can spread malaria.

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Self-Care

Caring for an insect bite or sting

Most bites and stings will heal on their own. Here are some things you can do at home.

• Get away from the insect.

  Move away from the stinging or biting insect. Bees will alert other bees, making them more likely to sting.

• Stay as calm and quiet as you can.

  Movement makes venom spread faster in the bloodstream.

• Remove the stinger or spine.

  If you were stung by a bee and the stinger is still in the skin, remove the stinger as soon as you can.

  If you were stung on the arm or leg, lower the limb at the time of the sting. This can slow the spread of venom. Hours later, if you have swelling, you can prop up the limb to help reduce swelling.

  After contact with a puss caterpillar, remove broken-off spines. Do this by placing cellophane tape or commercial facial peel over the area of the contact and pulling it off.

  If you were stung by a scorpion, see a doctor right away. There is now a medicine (antidote) for scorpion stings.

• Try cold, then heat.
  • Apply an ice pack to a bite or sting for 15 to 20 minutes once an hour for the first 6 hours. When you're not using ice, keep a cool, wet cloth on the bite or sting for up to 6 hours. Always keep a cloth between your skin and the ice pack. Don't apply ice for longer than 15 to 20 minutes at a time. Don't fall asleep with the ice on your skin.
  • After the first 6 hours, if you don't have swelling, try applying warmth to the site for comfort.
• Try a non-prescription medicine to relieve itching, redness, and swelling.
  • An antihistamine that you take by mouth, such as a non-drowsy one like loratadine (Claritin) or one that might make you sleepy like diphenhydramine (Benadryl), may help relieve itching, redness, and swelling.
  • A spray of local anesthetic containing benzocaine, such as Solarcaine, may help relieve pain. If your skin reacts to the spray, stop using it.
  • Hydrocortisone 1% cream or calamine lotion applied to the skin may help relieve itching and redness. You may need to check with your doctor first if you need to use the cream for a child younger than age 2 or for use in the genital area.

  These medicines may not be safe for children younger than age 6 or for people who have certain health problems. Before you use them, check the label. If you do use these medicines, always follow the directions about how much to use based on age and, in some cases, weight. You may need to check with your doctor about using these medicines.

• Try other remedies.

  Some people try a home remedy, such as putting witch hazel or underarm deodorant on the bite. Home remedies haven't been proven scientifically to help. But they usually won't hurt you if you want to try them.

• Watch for signs of a skin infection.

  Signs of infection include:

  • Increased pain, swelling, redness, or warmth around the bite.
  • Red streaks leading from the bite.
  • Pus draining from the bite.
  • A fever.
• Prevent infection.
  • Wash the area with clean water 2 times a day.
  • Don't break any blisters that develop.
  • Try not to scratch the bite area. Trim fingernails to prevent scratching and infection.
  • Apply a bandage, if needed. You may cover the area with a thin layer of petroleum jelly, such as Vaseline, and a non-stick bandage. Apply more petroleum jelly and replace the bandage as needed.

When to call during self-care

Call a doctor if you have any of the following symptoms during home treatment:

• New symptoms or they become more severe or frequent.
• Signs of a skin infection.
• Influenza (flu) symptoms, such as a fever, muscle aches, or chills.

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Watch

Prevention

You can reduce your or your child's chances of being stung and having a subsequent allergic reaction by preventing or avoiding exposure to the stinging insects.

• Be cautious when you are outdoors.

  Pay special attention to areas where stinging insects may be present, such as woods, orchards, flower gardens, picnic areas, or near trash containers or old buildings.

• Be careful around eaves, attics, window frames, crawl spaces, and vents, where insects may nest.
• Be cautious when eating outside.

  When eating outdoors, don't put your picnic out until you are ready to eat, and repack food as soon as you are finished serving. If you attend an outdoor event, keep away from the food serving areas and trash containers.

• Avoid scented cosmetics, deodorants, hair sprays, lotions, aftershave, and floral perfumes, which may attract stinging insects.
• Avoid brightly coloured clothing or fabrics with floral prints when you will be outdoors.

  Some stinging insects may be attracted to them. Clothing in a single neutral light colour such as white, beige, or khaki is less attractive to stinging insects.

• Wear the right clothing when outdoors.

  Avoid going barefoot or wearing sandals or open-toed shoes. Wear closed shoes, socks, and clothes that fully cover your body. Button long sleeves, tuck long pants inside boots, and wear gloves when you are gardening. Avoid loose clothes that might entangle a biting or stinging insect.

• If you are at increased risk of a severe allergic reaction (anaphylaxis), have someone else do yard work.
• Carefully unfold and inspect any clothing that has been left outdoors.

  Do this before putting it on or taking it indoors.

• Keep car windows closed.
• Avoid sudden or rapid movements around insects.

  Don't swat or flail your arms. Move away slowly unless you are being pursued.

• Use insect repellent and keep bug spray nearby when bees, wasps, and hornets are active.

  Choose one that works specifically on the types of insects that you or your child is allergic to. Read labels carefully—many general-purpose insecticides for home and garden use are not effective against common stinging insects.

• Inspect your home and yard for insect nests or places where insects may build nests.

  Consider having the inspection and removal done by a professional insect exterminator. Keep in mind that stinging insects are valuable in the environment, and it is generally not effective or desirable to control them over a wide area.

• Keep trash containers closed, and clean them frequently.
• Keep the area around trees or shrubs clear of fruit.

  Do not allow decaying fruit to accumulate, because it may attract bees and wasps.

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Preparing For Your Appointment

You can help your doctor diagnose and treat your condition by being prepared to answer the following questions:

• What type of insect or spider bit or stung you? Be prepared to describe it.
• When were you bitten or stung? How many times were you bitten or stung? Where on your body were you bitten or stung?
• Have you ever had a severe allergic reaction (anaphylaxis) to a similar bite or sting?
• What are your main symptoms?
• When did your symptoms begin? How have your symptoms developed, progressed, or changed since the bite or sting?
• What home treatment have you tried for the bite or sting? Did it help?
• What prescription or non-prescription medicines have you tried on the bite? Did they help?
• Have you travelled recently?
• Do you have any health risks?