Black Widow Spider Bite

Be aware, however, that this antivenin may not be readily available at most hospitals; there may be some delay or difficulty in obtaining it when needed.

Poisoning Due to Black Widow Spider Venom (Black Widow Spider Bites)

Black widow spiders are easily recognizable. They’re plump, black, and shiny, with an hourglass-shaped, red mark on their abdomens. Sometimes, this red mark may take a slightly different shape. In other cases, the spider may have red markings on its back too.

This type of spider gets its name from its historically reported mating behavior. After mating, females of some species kill and then eat their male partners, leaving them as “widows.” This behavior is dependent on several factors, including the species, the age of the female, and hunger level.

These spiders aren’t aggressive and only bite when they feel threatened. The bites usually aren’t fatal, but they can still cause some serious and uncomfortable symptoms.

If a black widow spider has bitten you, get medical treatment right away.

This spider type is found throughout the world. While they’re found all over the United States, they’re most common in the Southern and Western states.

In the U.S., healthcare spending accounts for 17.7% of the Gross Domestic Product (GDP), or the total value of goods and services produced by the entire nation for the entire year, according to the Centers for Medicare & Medicaid Services.

You’ll usually feel the sensation of a minor pinprick when a black widow spider first bites you. You might not realize that you’ve been bitten at first unless you caught the spider in the act. In some cases, the bite might be painful right away.

The area around the bite will likely redden and begin to swell.

You’ll develop more serious symptoms within a few hours of the bite. Sometimes, the more serious symptoms can develop in as little as 15 minutes after the bite occurs.

Most commonly, you’ll experience pain that’s not limited to the bite location. Your chest and abdomen, in particular, will be painful. The muscles in these areas will cramp and go rigid due to severe muscle spasms. Your back and shoulders may also hurt.

Other signs and symptoms you might experience include:

• difficulty breathing, which is due to paralysis of the diaphragm
• nausea
• chills
• a severe increase in blood pressure
• a headache, which may be partially due to a change in blood pressure
• sweating
• weakness
• a fever

In rare and extreme cases, black widow spider venom poisoning may lead to seizures and even death.

Death generally doesn’t occur in healthy adults. Young people, the elderly, and those with weakened immune systems are more susceptible to serious complications and death from a black widow spider bite.

Regardless, anyone who has been bitten, or who suspects they’ve been bitten by a black widow spider, should seek medical treatment immediately.

Black widow spiders are reclusive and not aggressive. They’ll never seek you out to bite you. Instead, they only bite in self-defense or when they feel threatened.

Black widow spiders live in dark, hidden spots, such as in piles of rocks, leaves, or wood. Don’t move or disturb these piles without wearing gloves, as you might accidentally touch a black widow spider and get bitten.

You should also wear gloves when you’re moving things out of dark corners in garages or basements. Black widow spiders may live in these areas.

These spiders might also hide in a variety of other dark places, such as:

• inside your shoes, especially if they’re stored somewhere dark
• in piles of unused blankets
• in the crevices of porch furniture
• between stones in a rock wall

Treatment for a black widow bite will vary depending on your health, symptoms, and the severity of the bite.

You may be given medication to help ease your pain. You might also be given medications to help lower the high blood pressure that sometimes accompanies a black widow spider bite.

If the bite is more severe, you may need muscle relaxants or antivenom, which is an antitoxin used to treat venomous bite. In some cases, you may even need to be hospitalized.

You should go to a doctor or emergency room right away if a black widow spider has bitten you.

There are some steps you can take immediately preceding your trip to the hospital or on the way to the hospital.

• Wash the bite thoroughly with soap.
• Apply a wet or damp ice pack for 10 minutes at a time, with 10-minute breaks in between.
• Elevate the location of the bite, if possible. For example, if you were bitten on your hand, keep your arm over your head. You should get to a hospital as soon as possible.

Last medically reviewed on December 13, 2018

How we reviewed this article:

Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

• Black widow. (n.d.).
  kids.nationalgeographic.com/animals/black-widow/
• Hey! A black widow spider bit me! (n.d.).
  kidshealth.org/en/kids/black-widow.html
• Mayo Clinic Staff. (2017). Spider bites.
  mayoclinic.org/diseases-conditions/spider-bites/symptoms-causes/syc-20352371
• Mayo Clinic Staff. (2018). Spider bites: First aid.
  mayoclinic.org/first-aid/first-aid-spider-bites/basics/art-20056618
• Spider bites. (n.d.).
  hopkinsmedicine.org/healthlibrary/conditions/adult/non-traumatic_emergencies/spider_bites_85,P00860/
• Venomous spiders. (2018).
  cdc.gov/niosh/topics/spiders/

Black Widow Spider Bite

The black widow spider produces a protein venom that affects the victim’s nervous system. This neurotoxic protein is one of the most potent venoms secreted by an animal.

Of the 30,000 types of spiders, the black widow is probably the one best known and feared. Although spiders are often blamed for all kinds of symptoms, from local itching to diffuse rashes, the fact is that spiders rarely bite humans, and in fact, most spider bites do not even break the skin.

The bites of very large spiders such as tarantulas can be painful. Otherwise, in the temperate regions, the only spiders to be feared are the black widow and the brown recluse.

• The black widow is a medium-sized spider whose body is about a half-inch long. The name is derived from the mistaken belief that the female invariably kills the male after mating. Although the spider is mostly found in the southern United States, it may be seen throughout the US. Five species are common to the US, with two of them being the most common:
  • The southern black widow has a shiny, black, globular abdomen with the distinctive red hourglass on the underside.
  • The northern black widow has a row of red spots down the middle of the upper surface of its abdomen and two crosswise bars on the undersurface. The markings can also be yellow or white, and the spider itself may be brown or have red legs.

  What Are the Symptoms of a Black Widow Spider Bite?

  The first symptom is acute pain at the site of the bite, although there may only be a minimal local reaction. Symptoms usually start within 20 minutes to one hour after the bite.

  The black widow spider produces a protein venom that affects the victim’s nervous system. This neurotoxic protein is one of the most potent venoms secreted by an animal. Some people are slightly affected by the venom, but others may have a severe response. The first symptom is acute pain at the site of the bite, although there may only be a minimal local reaction. Symptoms usually start within 20 minutes to one hour after the bite.

  • Local pain may be followed by localized or generalized severe muscle cramps, abdominal pain, weakness, and tremor. Large muscle groups (such as the shoulder or back muscles) are often affected, resulting in considerable pain. In severe cases, nausea, vomiting, fainting, dizziness, chest pain, and respiratory difficulties may follow.
  • The severity of the reaction depends on the age and physical condition of the person bitten. Children and the elderly are more seriously affected than young adults.
  • In some cases, abdominal pain may mimic such conditions as appendicitis or gallbladder problems. Chest pain may be mistaken for a heart attack.
  • Blood pressure and heart rate may be elevated. The elevation of blood pressure can lead to one of the most severe complications.
  • People rarely die from a black widow’s bite. Life-threatening reactions are generally seen only in small children and the elderly.

  QUESTION

  Should I See a Doctor If I Get Bitten by a Black Widow?

  If the person who was bitten by a black widow spider has more than minor pain or has whole-body symptoms, seek care at the nearest hospital’s emergency department.

  Treatment for serious reactions to a black widow spider’s bite will be beyond the scope of most medical offices and urgent care centers. Pain relief may require the use of narcotics and antivenin (antitoxin to counteract the effects of the spider venom).

  The decision to seek emergency care should be made early. If the person who was bitten by a black widow spider has more than minor pain or has whole-body symptoms, seek care at the nearest hospital’s emergency department. If symptoms are severe, call 911 for emergency medical transport so that evaluation and treatment can start en route to the hospital.

  Black Widow Spider Bite Home Remedies

  The options for home care are limited. Both cold and warm compresses have been recommended, as have hot baths. Obviously, over-the-counter pain relievers such as acetaminophen and ibuprofen may be of value in mild cases. Folk remedies have not proven to work.

  Bad Bugs and Their Bites

  Sex Drive Killers

  Cancerous Tumors

  Multiple Sclerosis

  Adult Skin Problems

  Habits That Wreck Your Teeth

  Manage Diabetes in 10 Minutes

  Erectile Dysfunction

  Type 2 Diabetes Warning Signs

  Health Benefits of Sex

  Scalp, Hair and Nails

  ADHD Symptoms in Children?

  What Is the Treatment for a Black Widow Spider Bite?

  In general, extensive medical evaluation is not necessary. The exceptions are when the history of a black widow bite is not clear, if the bite was not witnessed, and when associated symptoms require the exclusion of more serious disorders, such as heart attack.

  Black Widow Spider Bite Medications?

  The person bitten by a black widow spider, who has pain severe enough to seek treatment at an Emergency Department, will require narcotic pain relief. Muscle relaxants given by injection may also be of value. Although calcium gluconate given through an IV has long been advocated, it does not seem to produce much relief of symptoms.

  Use of antivenin

  The antivenin available for treatment of black widow spider bites is derived from horse serum. The venom produced by various species of black widow spiders is similar, so the antivenin prepared against one venom is effective against the others. Antivenin is produced by gradually increasing injections of the specific venom in a horse. The horse then starts producing the antivenin, which will be used in humans.

  Symptoms are often not easily relieved, even with narcotics. Some experts recommend that antivenin be used in any severe bite because one vial of the antitoxin produces significant and rapid relief of symptoms. It can even be used if there is delay in reaching the hospital. Yet other sources recommend that antivenin be used only in children, the elderly, and those with severe underlying medical conditions.

  Horse serum-based antivenin carries a significant risk of a severe allergic reaction (anaphylaxis) which can be life-threatening. Skin testing before the serum is administered is therefore recommended. Although another side effect known as serum sickness (characterized by skin lesions, fever, pain in the joints, and swollen lymph glands) is common when horse serum is used to treat rattlesnake bites, it is uncommon when used to treat black widow spider bites (probably because of the low dose needed for relief).

  Be aware, however, that this antivenin may not be readily available at most hospitals; there may be some delay or difficulty in obtaining it when needed.

  Note: The use of the black widow antivenin might sensitize the person against later use of rattlesnake antivenin. Obviously, the physician should discuss lifestyle habits that might affect the person’s risk of incurring a snakebite in the future. In many areas, black widow bites are much more common than rattlesnake bites.

  What Is the Follow-Up for a Black Widow Spider Bite?

  Follow-up is always necessary in cases where antivenin is used. Although serum sickness is uncommon with single-vial doses of horse serum, it may occur 7-12 days after exposure and is characterized by skin lesions, fever, pain in the joints, and swollen lymph glands. The symptoms may occur sooner in a sensitized person. The process is self-limited, goes away in 2-3 weeks, and may be treated with antihistamines and steroids.

  How Do I Prevent Spider Bites from Black Widows?

  Because black widow spiders bite if they are disturbed, care should be taken in reaching into dark areas. In areas where spider infestations are a problem, the use of a pest control service may also be useful.

  What Are the Complications from Black Widow Spider Bites?

  Complications in healthy adults are uncommon. If the black widow spider bite is not treated with antivenin, symptoms may last for several days but are seldom life threatening.

  Health Solutions From Our Sponsors

  • Penis Curved When Erect
  • Could I have CAD?
  • Treat Bent Fingers
  • Treat HR+, HER2- MBC
  • Tired of Dandruff?
  • Life with Cancer