Insect bites and stings

Introduction:

Insect bites or stings can be from a number of insects including bees, spiders, fleas, hornets, wasps, and mosquitoes. Some cause itching; others cause pain. The itching and pain occur because the insect has injected venom or another irritating substance into your skin, which causes an allergic reaction. In most cases, this reaction is bothersome but not dangerous. However, a severe reaction can cause anaphylaxis, resulting in shortness of breath and tightening of your throat. Anaphylaxis can be fatal, even on the first reaction. Severe reactions can affect the whole body and may occur in minutes. This is a medical emergency and you should call 911. Another type of allergic reaction is called angioedema, which involves swelling throughout your body, especially the face, lips, and around the eyes. More people have allergic reactions to stinging insects than to biting insects.

Signs and Symptoms:

• Red, swollen, warm lump
• Hives
• Itching, tenderness, pain
• Sores from scratching; can become infected
• Serious allergic reactions (called anaphylaxis) when symptoms spread. These can include difficulty breathing, dizziness, nausea, fever, muscle spasms, or loss of consciousness. Call for emergency medical help right away.

Causes:

Stinging insects include bumblebees, yellow jackets, hornets, wasps, and fire and harvester ants. Biting insects include conenose bugs, mosquitoes, horseflies, deerflies, spiders, ticks, bedbugs, and black flies.

Prevention

• Try not to provoke insects. For example, avoid rapid, jerky movements around insect hives or nests.
• Avoid perfumes, lotions, and scented soaps.
• Avoid areas where you know insects are.
• Use insect repellants and protective clothing. (See more details below.)
• Be careful when eating outdoors, especially with sweet drinks (such as sodas) or in areas near garbage cans.
• Make sure you have screens on all windows.
• To keep mosquito eggs from hatching, remove any standing water.
• Mosquitoes are most active at dawn and dusk, so avoid being outside during those times.
• Use citronella, linalool, and geraniol candles. In one study, citronella candles reduced the number of female mosquitoes cuaght in traps by 35%; linalool candles reduced female mosquitoes by 65%; and geraniol candles reduced female mosquitoes by 82%.

If you know that you have a serious allergy to an insect, carry an emergency epinephrine kit. Your doctor can prescribe one. Make sure that friends and family members know how to use an Epi-pen if you have had a reaction in the past. Wear a medical ID bracelet. For those with allergies, venom immunotherapy is up to 98% effective in preventing sting anaphylaxis.

If you are traveling to an area where malaria is common, ask your doctor about a malaria vaccine.

You can prevent insect bites and stings with proper clothing:

• Cover your head. Wear a full brimmed hat to help shield your neck as well.
• Wear long-sleeved shirts and long pants.
• Tuck pant cuffs into socks. This helps protect your ankles -- a common spot for bites or stings.
• Check your clothes and hair periodically for bugs.
• Use protective netting when sleeping or eating outdoors.

Applying insect repellent to your clothes instead of your skin can help prevent any skin irritation. When in an area infested with mosquitoes, sand flies, or ticks, use a chemical insect repellent such as DEET. DEET has been the most effective and broadly used insect repellent for the past 6 decades. Don't apply insect repellent to sunburned skin. When applying both sunscreen and bug repellent, apply the sunscreen first. Wait 30 minutes before applying the bug repellent.

Don't use bug repellent on children's hands because they may rub their eyes or put their hands in their mouths.

Treatment Approach:

In most cases, bites and stings can be easily treated at home. However, don't try to treat a suspicious bite on your own; when in doubt, call your doctor. In the case of a severe allergic reaction such as anaphylaxis, you must seek emergency medical help. Do not try to treat anaphylaxis with complementary therapies alone. If such an emergency occurs:

• Check the person's airway, breathing, and pulse. If necessary begin CPR and call 911.
• Use the person's epinephrine pen or other emergency kit if they have one. (Anyone who has had a serious allergic reaction to an insect sting should carry an Epi-pen or its equivalent at all times.)
• Try to keep the person calm.
• Remove any rings and other constricting items in case of swelling.
• Stay with the person until medical help arrives.

Lifestyle

Redness, minor swelling, pain, or itching at the site of the bite generally go away in 3 - 7 days with no treatment, even if the affected area is large. To relieve your symptoms, follow these steps:

• Remove the stinger if it is still present by scraping the back of a credit card or other straight edged object across the stinger. Don't use tweezers to pull out the stinger -- that may release more venom.
• Wash thoroughly with soap and water to avoid infection. Watch for signs of infection, such as increased redness or red streaking along your skin, over the next several days.
• Place an ice pack, wet compress, or ice wrapped in a cloth on the site of the sting for 10 minutes, then off for 10 minutes.
• Take an antihistamine or apply a cream that reduces itching (such as Calamine or Benadryl ointment) if the bite itches. You can also use a paste made of 3 parts baking soda to 1 part water.

Medications

• Antihistamines can be used to reduce itching and swelling.
• If you develop an infection at the site of the bite, your doctor may prescribe antibiotics.
• In case of a severe reaction, emergency medical personnel may give intravenous (IV) antihistamines and epinephrine (adrenaline).

Nutrition and Dietary Supplements

Including some nutrients in your diet may help support your immune system and possibly reduce any inflammation or allergic reaction you may have from an insect bite or sting, although there is no scientific evidence that they will be effective. Talk to your doctor before taking a supplement to make sure that it is safe for you and will not interact with any medications that you regularly take.

• Quercetin (400 - 500 mg per day) -- a flavonoid and antioxidant found in many plants that may help reduce allergic reactions. The water-soluble kind of quercetin, sometimes called hesperidin methylchalcone (HMC) or quercetin chalcone, is more easily absorbed and has stronger effects for some people.
• Vitamin C (1,000 mg 2 - 6 times per day for a short period) -- Supports immune system function and also enhances the effect of quercetin. Lower dose if diarrhea develops
• Zinc (30 mg per day) -- Animal studies suggest that zinc may help protect against gastrointestinal symptoms (stomach cramps, nausea, vomiting, or diarrhea) that sometimes accompany anaphylaxis.
• Omega-3 fatty acids (fish oil) -- may help reduce inflammation in the body, so some experts think they might also protect against severe allergic reactions. In one study, there was a lower death rate from anaphylactic shock in animals on a high omega-3 fatty acid diet compared to those on a high omega-6 fatty acid diet. But researchers don't know if the same would be true of humans. More studies are needed. Omega-3 fatty acids can have a blood thinning effect and should be used with caution in people with bleeding disorders or who use blood thinning medications. Talk to your doctor.

Herbs

The use of herbs is a time honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care practitioner.

Some herbs that have been used traditionally at the site of an insect bite or sting to reduce symptoms include:

• Lemon balm (Melissa officinalis)
• Stinging nettle ( Urtica dioica; Urtica urens)
• Tea tree oil (Melaleuca alternifolia)
• Calendula (Calendula officinalis)
• Plantain (Plantago major)

Some essential oils may help repel insects. Dilute the oil before applying to your skin; never apply pure oil directly. These oils include:

• Eucalyptus (Eucalyptus globulus)
• Clove (Eugenia caryophyllata)
• Citronella (Cymbopogon spp.)
• Neem oil or cream (Azadirachta indica)

Homeopathy

Few studies have examined the effectiveness of specific homeopathic remedies. A professional homeopath, however, may recommend one or more of the following treatments for insect bites and stings based on his or her knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. In homeopathic terms, a person's constitution is his or her physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.

• Apis mellifica -- for stinging pains with rapid swelling and affected area that is warm to the touch; this remedy is most appropriate for individuals who feel better with cold applications; Apis is recommended if hives are present or if Ledum does not reduce pain or swelling after 4 hours
• Hypericum -- for bites accompanied by sharp, shooting pains that often occur in sensitive areas, such as at the ends of fingers or toes
• Ledum -- most commonly used homeopathic agent for bites and stings from bees, mosquitoes, wasps, or spiders; affected area is cold to the touch but cold applications or immersion in cold water improves symptoms
• Staphysagria -- for children with large, itchy mosquito bites that may create large welts
• Urtica urens -- for red, swollen bites with itching and stinging; may be used instead of Apis to treat hives

Alternative Names:

Bites and stings - insect; Stings and bites - insect