Insect Bites and Stings and Spider Bites

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Topic Overview

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

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

Examples of problems that are more serious include:

  • A severe allergic reaction ( anaphylaxis ). Severe allergic reactions are not common but can be life-threatening and require emergency care. Signs or symptoms may include:
    • Shock , which may occur if the circulatory system cannot get enough blood to the vital organs.
    • Coughing, wheezing, trouble breathing, or 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).
    • Lightheadedness and confusion .
    • Nausea, diarrhea, and stomach cramps.
    • Raised, red, itchy bumps called hives and reddening of the 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:
  • 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 and 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 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 , a reaction to the medicines (antiserum) used to treat a bite or sting. Serum sickness may cause hives and flu-like symptoms 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 ). For more information, see the topic West Nile Virus .
  • A parasite infection. Infected mosquitoes can spread malaria . For more information, see the topic Malaria .

Check your symptoms to decide if and when you should see a doctor.

Health Tools

Health Tools help you make wise health decisions or take action to improve your health.

Decision Points focus on key medical care decisions that are important to many health problems.

Check Your Symptoms

Have you been bitten or stung by an insect or spider?
Yes
Insect or spider bite or sting
No
Insect or spider bite or sting
How old are you?
Less than 1 year old
Less than 1 year
1 to 11 years
1 to 11 years
12 years or older
12 years or older
Are you male or female?
Male
Male
Female
Female
Do you have a concern about a tick bite?
Yes
Tick bite concern
No
Tick bite concern
Did the bite or sting involve the eyeball?
Yes
Bite or sting to eyeball
No
Bite or sting to eyeball
Could you be having a severe allergic reaction ?
This is more likely if you have had a bad reaction to something in the past.
Yes
Possible severe allergic reaction (anaphylaxis)
No
Possible severe allergic reaction (anaphylaxis)
Do you have symptoms of shock?
The symptoms in an adult or older child are different than the symptoms in a young child .
Yes
Symptoms of shock
No
Symptoms of shock
Have you ever had a severe allergic reaction to a bite or sting?
A severe allergic reaction affects the whole body. Your doctor may have called it anaphylaxis.
Yes
History of severe allergic reaction to bite or sting
No
History of severe allergic reaction to bite or sting
Are you having any symptoms of an allergic reaction now, even mild ones?
If you've ever had a severe reaction to the same thing that's causing your symptoms now, treat this as an emergency. Mild symptoms quickly may become severe.
Yes
History of severe reaction with symptoms now
No
History of severe reaction with symptoms now
Is there any serious swelling?
This could include swelling that is not near the bite or sting area, or swelling that began at the bite or sting site but is expanding well beyond that area. (Some swelling at the site of the bite or sting is normal.)
Yes
New or expanding swelling not near bite or sting
No
New or expanding swelling not near bite or sting
Are the lips, tongue, mouth, or throat swollen?
Yes
Swelling of lips, tongue, mouth, or throat
No
Swelling of lips, tongue, mouth, or throat
Did the lips, tongue, mouth, or throat swell quickly?
Yes
Rapid swelling of lips, tongue, mouth, or throat
No
Rapid swelling of lips, tongue, mouth, or throat
Does swelling involve the palms of the hands, the soles of the feet, or the area from one large joint to another, such as from the ankle to the knee?
Yes
Swelling is across two joints, on soles of feet, or on palms of hands
No
Swelling is across two joints, on soles of feet, or on palms of hands
Is the swelling getting worse (over hours or days)?
Yes
Swelling is getting worse
No
Swelling is getting worse
Did you get an epinephrine shot to treat the reaction?
Yes
Has had epinephrine shot
No
Has had epinephrine shot
Have you been bitten or stung by a poisonous spider (such as a black widow or brown recluse spider), a scorpion, or a caterpillar?
Yes
Bitten or stung by poisonous spider, scorpion, or caterpillar
No
Bitten or stung by poisonous spider, scorpion, or caterpillar
Are there any hives?
Hives are raised, red, itchy patches of skin. They usually have red borders and pale centers. They may seem to move from place to place on the skin.
Yes
Hives
No
Hives
Do the hives cover many places on your body?
Yes
Hives in many places
No
Hives in many places
Did the hives appear within 3 hours after the bite or sting?
Yes
Hives developed within 3 hours of bite or sting
No
Hives developed within 3 hours of bite or sting
Are there any symptoms of infection ?
Yes
Symptoms of infection
No
Symptoms of infection
Do you think you may have a fever?
Yes
Possible fever
No
Possible fever
Are there red streaks leading away from the area or pus draining from it?
Yes
Red streaks or pus
No
Red streaks or pus
Do you have diabetes, a weakened immune system , peripheral arterial disease, or any surgical hardware in the area?
"Hardware" includes things like artificial joints, plates or screws, catheters, and medicine pumps.
Yes
Diabetes, immune problems, peripheral arterial disease, or surgical hardware in affected area
No
Diabetes, immune problems, peripheral arterial disease, or surgical hardware in affected area
Have you developed any flu-like symptoms after the bite or sting, such as fever, shaking chills, muscle or joint pain, headache, or a general feeling of illness?
This could happen within minutes of the bite or sting or up to 3 weeks later.
Yes
Flu-like symptoms
No
Flu-like symptoms
Did these symptoms begin within minutes after the bite or sting?
Yes
Flu-like symptoms began within minutes after bite or sting
No
Flu-like symptoms began within minutes after bite or sting
Do you have other symptoms, such as belly pain, vomiting, or diarrhea?
Yes
Has other symptoms, such as belly pain, vomiting, or diarrhea
No
Has other symptoms, such as belly pain, vomiting, or diarrhea
Did these symptoms begin within minutes after the bite or sting?
Yes
Other symptoms began within minutes after bite or sting
No
Other symptoms began within minutes after bite or sting
Have tiny red or purple spots or bruises appeared suddenly?
Yes
Sudden appearance of red or purple spots or bruising
No
Sudden appearance of red or purple spots or bruising
Is there a blister, a painful sore, or a purple discoloration at the site of a bite or sting?
Yes
Blister, painful sore, or purple discoloration at bite or sting site
No
Blister, painful sore, or purple discoloration at bite or sting site
Are you having new muscle spasms or stiffness?
Yes
Muscle spasms or stiffness after bite or sting
No
Muscle spasms or stiffness after bite or sting
Do you have pain at the site of the bite or sting?
The pain may feel like a burning pain. It may be very bad for several minutes right after the bite. You may still have some pain hours later.
Yes
Pain or burning pain at site of bite or sting
No
Pain or burning pain at site of bite or sting
How bad is the pain on a scale of 0 to 10, if 0 is no pain and 10 is the worst pain you can imagine?
Signs of pain in an adult or child are different than signs of pain in a baby or toddler .
8 to 10: Severe pain
Severe pain
5 to 7: Moderate pain
Moderate pain
1 to 4: Mild pain
Mild pain
Has the pain lasted for more than 8 hours?
Yes
Pain for more than 8 hours
No
Pain for more than 8 hours
Is the pain getting worse?
Yes
Pain is getting worse
No
Pain is getting worse
Have you tried home treatment for more than 2 days?
Home treatment includes things like using ice on the area, taking an antihistamine, and taking pain medicine such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin).
Yes
Home treatment for more than 2 days
No
Home treatment for more than 2 days
Did you get more than one bite or sting?
This does not include mosquito bites.
Yes
More than 1 bite or sting
No
More than 1 bite or sting
Was there more than one bite or sting from bees, wasps, hornets, yellow jackets, or fire ants?
Yes
2 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
No
2 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
Did you get at least 5 bites or stings from bees, wasps, hornets, yellow jackets, or fire ants?
Yes
5 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
No
5 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
Did you get at least 10 bites or stings from bees, wasps, hornets, yellow jackets, or fire ants?
Yes
10 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
No
10 or more bites or stings from bees, wasps, hornets, yellow jackets, or fire ants
Do you think you may need a tetanus shot ?
Yes
May need tetanus shot
No
May need tetanus shot
Have symptoms lasted for more than a week after the bite or sting?
Yes
Symptoms for more than 1 week after bite or sting
No
Symptoms for more than 1 week after bite or sting

Many things can affect how your body responds to a symptom and what kind of care you may need. These include:

  • Your age. Babies and older adults tend to get sicker quicker.
  • Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
  • Medicines you take. Certain medicines, herbal remedies, and supplements can cause symptoms or make them worse.
  • Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
  • Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.

Try Home Treatment

You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.

  • Try home treatment to relieve the symptoms.
  • Call your doctor if symptoms get worse or you have any concerns (for example, if symptoms are not getting better as you would expect). You may need care sooner.
HomeTreatment
RelatedInformation

Symptoms of a severe allergic reaction (anaphylaxis) may include:

  • The sudden appearance of raised, red areas (hives) all over the body.
  • Rapid swelling of the throat, mouth, or tongue.
  • Trouble breathing.
  • Passing out (losing consciousness). Or you may feel very lightheaded or suddenly feel weak, confused, or restless.

A severe reaction can be life-threatening. If you have had a bad allergic reaction to a substance before and are exposed to it again, treat any symptoms as an emergency. Even if the symptoms are mild at first, they may quickly become very severe.

Symptoms of infection may include:

  • Increased pain, swelling, warmth, or redness in or around the area.
  • Red streaks leading from the area.
  • Pus draining from the area.
  • A fever.

Pain in adults and older children

  • Severe pain (8 to 10): The pain is so bad that you can't stand it for more than a few hours, can't sleep, and can't do anything else except focus on the pain.
  • Moderate pain (5 to 7): The pain is bad enough to disrupt your normal activities and your sleep, but you can tolerate it for hours or days. Moderate can also mean pain that comes and goes even if it's severe when it's there.
  • Mild pain (1 to 4): You notice the pain, but it is not bad enough to disrupt your sleep or activities.

Pain in children under 3 years

It can be hard to tell how much pain a baby or toddler is in.

  • Severe pain (8 to 10): The pain is so bad that the baby cannot sleep, cannot get comfortable, and cries constantly no matter what you do. The baby may kick, make fists, or grimace.
  • Moderate pain (5 to 7): The baby is very fussy, clings to you a lot, and may have trouble sleeping but responds when you try to comfort him or her.
  • Mild pain (1 to 4): The baby is a little fussy and clings to you a little but responds when you try to comfort him or her.

Certain health conditions and medicines weaken the immune system's ability to fight off infection and illness. Some examples in adults are:

  • Diseases such as diabetes, cancer, heart disease, and HIV/AIDS.
  • Long-term alcohol and drug problems.
  • Steroid medicines, which may be used to treat a variety of conditions.
  • Chemotherapy and radiation therapy for cancer.
  • Other medicines used to treat autoimmune disease.
  • Medicines taken after organ transplant.
  • Not having a spleen.

Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.

Symptoms of shock (most of which will be present) include:

  • Passing out (losing consciousness).
  • Feeling very dizzy or lightheaded, like you may pass out.
  • Feeling very weak or having trouble standing.
  • Not feeling alert or able to think clearly. You may be confused, restless, fearful, or unable to respond to questions.

Shock is a life-threatening condition that may occur quickly after a sudden illness or injury.

Symptoms of shock in a child may include:

  • Passing out (losing consciousness).
  • Being very sleepy or hard to wake up.
  • Not responding when being touched or talked to.
  • Breathing much faster than usual.
  • Acting confused. The child may not know where he or she is.

You may need a tetanus shot depending on how dirty the wound is and how long it has been since your last shot.

  • For a dirty wound that has things like dirt, saliva, or feces in it, you may need a shot if:
    • You haven't had a tetanus shot in the past 5 years.
    • You don't know when your last shot was.
  • For a clean wound, you may need a shot if:
    • You have not had a tetanus shot in the past 10 years.
    • You don't know when your last shot was.

Sudden tiny red or purple spots or sudden bruising may be early symptoms of a serious illness or bleeding problem. There are two types.

Petechiae (say "puh-TEE-kee-eye"):

  • Are tiny, flat red or purple spots in the skin or the lining of the mouth.
  • Do not turn white when you press on them.
  • Range from the size of a pinpoint to the size of a small pea and do not itch or cause pain.
  • May spread over a large area of the body within a few hours.
  • Are different than tiny, flat red spots or birthmarks that are present all the time.

Purpura (say "PURR-pyuh-ruh" or “PURR-puh-ruh”):

  • Is sudden, severe bruising that occurs for no clear reason.
  • May be in one area or all over.
  • Is different than the bruising that happens after you bump into something.

Seek Care Now

Based on your answers, you may need care right away. The problem is likely to get worse without medical care.

  • Call your doctor now to discuss the symptoms and arrange for care.
  • If you cannot reach your doctor or you don't have one, seek care in the next hour.
  • You do not need to call an ambulance unless:
    • You cannot travel safely either by driving yourself or by having someone else drive you.
    • You are in an area where heavy traffic or other problems may slow you down.

Call 911 Now

Based on your answers, you need emergency care.

Call 911 or other emergency services now.

Seek Care Today

Based on your answers, you may need care soon. The problem probably will not get better without medical care.

  • Call your doctor today to discuss the symptoms and arrange for care.
  • If you cannot reach your doctor or you don't have one, seek care today.
  • If it is evening, watch the symptoms and seek care in the morning.
  • If the symptoms get worse, seek care sooner.
HomeTreatment
RelatedInformation

Make an Appointment

Based on your answers, the problem may not improve without medical care.

  • Make an appointment to see your doctor in the next 1 to 2 weeks.
  • If appropriate, try home treatment while you are waiting for the appointment.
  • If symptoms get worse or you have any concerns, call your doctor. You may need care sooner.
HomeTreatment
RelatedInformation

Seek Care Now

Based on your answers, you may need care right away. The problem is likely to get worse without medical care.

  • Call your doctor now to discuss the symptoms and arrange for care.
  • If you cannot reach your doctor or you don't have one, go to the emergency room now. You may have a reaction after the epinephrine wears off.
  • You do not need to call an ambulance unless:
    • You cannot travel safely either by driving yourself or by having someone else drive you.
    • You are in an area where heavy traffic or other problems may slow you down.
Eye Injuries
Tick Bites

Home Treatment

Common bites and stings

Most bites and stings will heal on their own without a visit to a doctor. There are several things you can do to relieve pain and itching and prevent infection from a bite or sting.

Insect or spider bites or stings or contact with caterpillars

  • Move away from the stinging or biting insect. Bees will alert other bees, making them more likely to sting.
  • Remain as calm and quiet as possible. Movement increases the spread of venom in the bloodstream.
  • If you have been stung by a bee and the stinger is still in the skin, remove the stinger as quickly as possible.
  • If you have been stung on the arm or leg, lower the limb at the time of the sting to slow the spread of venom. Hours later, if swelling is present, you can elevate the limb to help reduce swelling.
  • After contact with a puss caterpillar , remove broken-off spines by placing cellophane tape or commercial facial peel over the area of the contact and pulling it off.
  • If you have been stung by a scorpion, see a doctor right away. There is now a medicine (antidote) for scorpion stings.

Relieve pain, itching, and swelling

  • Apply an ice pack to a bite or sting for 15 to 20 minutes once an hour for the first 6 hours. When 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. Do not apply ice for longer than 15 to 20 minutes at a time. Do not fall asleep with the ice on your skin.
  • Elevate the area of the bite or sting to decrease swelling.
  • Try a nonprescription medicine for the relief of itching, redness, and swelling. Be sure to follow the nonprescription medicine precautions .
    • An antihistamine taken by mouth, such as a nondrowsy one like loratadine (Claritin) or one that might make you sleepy like diphenhydramine (Benadryl), may help relieve itching, redness, and swelling. Don't give antihistamines to your child unless you've checked with the doctor first.
    • 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. Note: Do not use the cream on children younger than age 2 unless your doctor tells you to. Do not use in the rectal or vaginal area in children younger than age 12 unless your doctor tells you to.
  • After the first 6 hours, if swelling is not present, try applying warmth to the site for comfort.
Medicine you can buy without a prescription
Try a nonprescription medicine to help treat your fever or pain:

Talk to your child's doctor before switching back and forth between doses of acetaminophen and ibuprofen. When you switch between two medicines, there is a chance your child will get too much medicine.
Safety tips
Be sure to follow these safety tips when you use a nonprescription medicine:
  • Carefully read and follow all directions on the medicine bottle and box.
  • Do not take more than the recommended dose.
  • Do not take a medicine if you have had an allergic reaction to it in the past.
  • If you have been told to avoid a medicine, call your doctor before you take it.
  • If you are or could be pregnant, do not take any medicine other than acetaminophen unless your doctor has told you to.
  • Do not give aspirin to anyone younger than age 20 unless your doctor tells you to.

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

Prevent a skin infection

  • Wash the area with clean water 2 times a day.
  • After washing, wipe the area with rubbing alcohol or first-aid antiseptic.
  • Trim fingernails to prevent scratching, which can lead to infection.
  • Do not break any blisters that develop.
  • You may cover the wound with a thin layer of petroleum jelly, such as Vaseline, and a nonstick bandage. Apply more petroleum jelly and replace the bandage as needed.

For home treatment of lice, scabies, tick bites, bedbugs, or kissing bugs, see the topics Body Lice , Head Lice , Pubic Lice , Scabies , Tick Bites , Bedbugs , and Kissing Bugs .

Symptoms to watch for during home treatment

Call your doctor if any of the following occur during home treatment:

Prevention

Take the following measures to help prevent bites and stings.

  • Apply insect repellent before going into the woods or other areas where you may come in contact with insects. Use insect repellents according to directions, particularly when applying repellent to children.
    • Apply repellents safely.
    • Use a lower-concentration repellent on children.
    • Do not put repellent on small children's hands, since they often put their hands in their mouths.
    • Wash the insect repellent off with soap and water after returning indoors.
  • Wear light-colored, smooth-finished clothes that cover your body, such as long-sleeved shirts and long pants. Button long sleeves and tuck long pants inside boots. Avoid loose clothes that might entangle a biting or stinging insect. Avoid bright colors. Avoid going barefooted or wearing sandals outdoors. Some outdoor stores may sell clothing treated with a repellent.
  • Avoid wearing perfumed lotions, aftershave, or scented hair products during the warm months.
  • Take positive steps to manage your surroundings.
    • Always close car windows.
    • Do not put your picnic out until you are ready to eat. Repack picnic food as soon as you are finished serving.
    • Avoid flowering plants.
    • If you have a severe allergic reaction ( anaphylaxis ) to insect bites or stings, have someone else mow lawns or clip hedges.
  • Avoid swatting at insects or flailing your arms around them. Instead, retreat slowly and calmly when insects act threatening.

Additional measures include those to:

If you have had a severe allergic reaction (anaphylaxis) to bites or stings in the past:

Preparing For Your Appointment

To prepare for your appointment, see the topic Making the Most of 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 nonprescription medicines have your tried on the bite? Did they help?
  • Have you traveled recently?
  • Do you have any health risks ?

Credits

ByHealthwise Staff

Primary Medical Reviewer William H. Blahd, Jr., MD, FACEP - Emergency Medicine

Adam Husney, MD - Family Medicine

E. Gregory Thompson, MD - Internal Medicine

Kathleen Romito, MD - Family Medicine

Specialist Medical Reviewer H. Michael O'Connor, MD - Emergency Medicine

Current as ofApril 13, 2017

Current as of: April 13, 2017

Author: Healthwise Staff

Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine & Adam Husney, MD - Family Medicine & E. Gregory Thompson, MD - Internal Medicine & Kathleen Romito, MD - Family Medicine & H. Michael O'Connor, MD - Emergency Medicine