Spider Bite First Aid and Safety

First Aid and Safety

Black widow spiders can be identified by the red hourglass marking on the underside of its abdomen.
A picture of a black widow spider, which can be identified by its jet black color and the red hourglass marking on the underside of its abdomen. Photo © Vincent Iannelli, MD

It can often seem like spiders are everywhere, and when you consider that more than 100,000 species of spiders have been identified, they probably are.

Many parents routinely find spiders in their garden and many places where spiders like to hide. Favorite hiding spots for many spiders include woodpiles and basements, attics, and even closets in our homes.

Fortunately, extremely few of these spiders are dangerous though.

In the Unites States, just two species of spiders are poisonous enough to cause harm. They include the black widow spider (Latrodectus mactans) and the brown recluse spider (Loxosceles reclusa).

It is important to remember than even dangerous black widow and brown recluse spiders aren't wandering around your house trying to attack your kids. They usually like to live in places where they won't be disturbed. Unless your child is crawling through boxes in a closet or attic, or some place else where he may have disturbed a spider, it is unlikely that any bites on his skin were caused by a "bad spider."

And they probably weren't caused by a spider at all, as many experts think that spider bites are over-diagnosed. Many other conditions, including other insect bites and MRSA infections.

Spider Bite Symptoms

Surprisingly, most spider bites aren't that painful. It may feel like a pinprick and they are often unnoticed when the spider actually bites your child.

Common spider bite symptoms can include a single bite mark with:

  • swelling
  • redness
  • itching
  • pain

In fact, most spider bites will resemble a bee sting. Your child may also develop hives and other allergy symptoms if he is allergic to the spider bite.

Symptoms of a black widow spider bite might also include severe muscle pain and cramps, which develop within a few hours of the bite.

Other symptoms may include weakness, vomiting, trouble breathing, abdominal pain, and high blood pressure.

Brown recluse spider bites can be painful. In addition to pain, these spider bites may cause burning and itching. Another characteristic finding is that the spider bite may look like a bull's eye, with a red ring around a white center that turns into an ulcer.

Diagnosis of a Spider Bite

The most obvious way to diagnosis a spider bite is to observe a spider biting your child. Since spiders are seen so commonly in many of our homes, simply seeing a spider and then noticing a bite on your child doesn't necessarily mean that your child has a spider bite.

As hard as it sometimes is to tell if a child even has a spider bite, it can be even harder to determine what type of spider actually bit him. Again, seeing the spider can help, as "bad spiders" have very characteristic features. The black widow spider is jet black, with a red hourglass marking on the underside of their abdomen. Brown recluse spiders are smaller, are yellowish-tan to dark brown, and have a violin shaped marking on their back.

Should you try to catch a spider to help your doctor identify it? Probably not, as you are more likely to bring your pediatrician a crushed spider that is impossible to identify than anything useful. And you should likely be concentrating on taking care of your child after he has been bitten, instead of chasing after the spider.

Spider Bite Treatments

For most spider bites, you can follow some simple home treatments, including:

  • washing the spider bite with soap and water
  • apply an ice cube to the bite for about 20 minutes
  • give your child a pain medicine, such as acetaminophen (Tylenol) or ibuprofen (Motrin or Advil)
  • apply a topical antibiotic ointment to the bite two or three times a day
  • apply a topical steroid cream to help control itching and redness a few times a day
  • continue home treatments for one or two days, the typical time that it takes a spider bite to go away

Of course, you should seek medical attention if you think your child was bitten by a black widow spider or brown recluse spider. Most parents overlook the fact that your local poison control center (1-800-222-1222) can be a good resource if you think your child was bitten by a poisonous spider though.

What You Need To Know

  • Even the poisonous black widow spiders and brown recluse spiders rarely cause life-threatening symptoms or death.
  • In addition to seeking medical attention for a black widow spider or brown recluse spider bite, see your pediatrician if a spider bite isn't getting better in a few days.
  • Kids may need a tetanus shot after a spider bite.
  • Spiders usually bite just once, so if a child has multiple bites, then it likely isn't from spider bites.
  • Although parents often look for the double fang marks in trying to identify a spider bite, they usually aren't seen, and even when you see "fang marks," it doesn't mean that your child was bitten by a spider.
  • Teach your kids to avoid spiders by shaking out shoes and clothing that are lying on the floor and not storing boxes or other items on the closet floor or underneath your child's bed. You can help keep spiders out of your child's crib or bed by making sure any bedding doesn't touch the floor.


Common spider bites. Diaz JH - Am Fam Physician - 15-MAR-2007; 75(6): 869-73

Habif: Clinical Dermatology, 4th ed.

Kliegman: Nelson Textbook of Pediatrics, 18th ed.

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