Every spring and summer, creepy spider sightings and a few seriously damaging spider bites crop up around the country. Fortunately, most common spider bites aren’t dangerous. However, bites can be painful, and some may cause far-reaching health effects. If you think you may have a spider bite — or you just want to avoid one — here’s what you need to know.
Where Spiders Live
Black widows appear throughout North America, but they’re most common to southern and western areas of the U.S. Brown recluses tend to show up in midwestern and southeastern states, but are occasionally spotted elsewhere. Hobo spiders hang out in the Pacific Northwest, while wolf spiders, found in various habitats, are especially attracted to prairies. Tarantulas favor hot, dry southwestern states. Check the website of your state health department for local spider specifics.
Indoors, you can find spiders under eaves, in your attic or in dusty, neglected areas. Outdoors, anything by the water attracts spiders. “Lake houses tend to have lots of spiders,” says Ohio dermatologist Dr. Amy Kassouf. Spiders like spinning webs in areas with plenty of bugs, she adds, so watch out for those nooks and crannies.
Identifying Spider Bites
“Was it really a spider bite?” is the first question. Other insect bites are frequently mistaken for spider bites. Less than one-quarter of medical case studies on spider bite cases fulfill the criteria for a verified spider bite, according to a review in the May 2016 issue of Toxicon. Suspected spider bites could actually be tick bites, chigger bites or mosquito bites.
Authors of a May 2017 article in JAMA Dermatology developed a mnemonic device (“NOT RECLUSE”) to offer diagnostic guideposts for doctors and other health care providers. Among highlights: A typical brown recluse spider bite usually involves only one lesion (or bite site) or two at the most. In North America, credible bites usually occur from April to October. The center of a recluse bite is typically pale, blue-white or purple, rather than red. A raised area is uncommon in recluse bites, which are actually flat or slightly sunken. By three months, only the largest recluse bites have not healed. Recluse bites usually don’t leak pus or other fluid.
If you actually see the spider that bit you, taking it with you as you seek medical care could be helpful for guiding treatment. But Dr. Andrew Murphy, an allergy and immunology specialist in West Chester, Pennsylvania, says that doesn’t often happen. “In 20 years, I’ve never had someone bring in a spider for me,” he says.
[See: 10 (Mostly) Natural Ways to Evade Mosquitoes.]
Spider Bite Symptoms
Often, people aren’t aware of insect bites immediately, but later notice a small bump or red spot. If the bite is itchy rather than painful, it’s more likely a mosquito bite than a spider bite, Kassouf says.
Spider bites tend to have a central puncture area where the stinger was inserted. Bites from more venomous spiders tend to hurt and swell more, she says.
Venomous Spiders
Black widows. With their shiny bodies, long legs and red hourglass markings, black widow spiders are easy to identify. “Their bites are very, very painful,” Murphy says. Kids have been bitten in gym locker rooms, he says, as the spiders are attracted to dark, moist areas. Woodpiles are also favorite haunts.
At first, skin around a bite swells at the site, and you may notice one or two fang marks along with burning, swelling and redness. Later, pain spreads, eventually reaching your back and belly. You could experience severe cramping or rigidity in your abdominal muscles.
Other symptoms can include heavy sweating, nausea, tremors, difficulty breathing, fever, restlessness and a rise in blood pressure. Pain usually lasts up to 12 hours, with symptoms possibly persisting for several days.
If you suspect you’ve been bitten by a venomous spider, wash the bite and elevate the area to keep venom from spreading. Call Poison Control at 800-222-1222 for advice. You may be told to seek immediate emergency care. Treatment can include anti-venom for black widow spider bites, pain medicine, muscle relaxants, steroids, antibiotics and a tetanus booster shot, depending on your symptoms.
Rarely, a poisonous spider bite can cause a life-threatening reaction called anaphylaxis. “If you start getting hives, lip swelling, tongue swelling, short of breath, wheezing, light-headed, dizzy — obviously, that’s a bad thing,” Murphy says. Call 911 for this medical emergency.
Brown recluses. Brown recluse spiders are known for the striking violin pattern on their backs and their rare but dangerous bites. True to their name, these spiders are reclusive rather than aggressive, usually biting only when threatened and next to someone’s skin.
Some bites may be painless or have a slight burning feel at first. A small blister may form. A few hours later, severe pain and itching can develop, along with nausea and vomiting, fever and muscle pains.
Even in small quantities, brown recluse venom is toxic and destructive. Enzymes in the venom attack nearby cells and destroy skin, fat and blood vessels around the bite, leading to necrosis. With necrosis, Kassouf says, the bite area usually turns dark purple to black in the center, and it starts to look more like a scab or deep bruise.
As the body’s immune system responds to toxins, severe side effects could include red blood cell destruction, blood-clotting problems, acute kidney damage and death. Deaths from brown recluse bites are rare and occur most often in small children.
In some cases, skin and cartilage damage can be severe, necessitating surgery and leaving permanent scars and other lifelong aftereffects. Emergency treatment is similar to that for a black widow spider bite to stem the body’s reaction, treat complications and prevent prolonged health damage.
Red widows. Lesser-known red widow spiders have reddish-orange heads, chest and legs contrasted with a black abdomen, which may have red-yellow spots. Found in central Florida dunes, palmettos and shrubs, female red widows are venomous.
Non-Poisonous Spider Bites
Wolf spider bite. Wolf spiders tend to hunt at night. They resemble large, brown recluse spiders but don’t carry the distinctive violin-shaped marking. Wolf spiders are only aggressive when threatened. Their bites are painful but not venomous.
Hobo spider bite. Hidden cracks, such as those found in railroad tracks, brush piles and rock walls, are habitats for hobo spiders. During their mating season in late spring and summer, they may come indoors. Hobo spider bites have been known to cause persistent headaches that last up to a week and don’t respond to pain medicine.
Tarantula bite. Tarantulas, which tend to be desert dwellers, live in ground-level nests. These hairy spiders, larger than most, come in a variety of colors and can be up to 5 inches long. Fortunately, tarantula bites aren’t venomous. However, they can cause allergic reactions.
Allergic Reactions to Spider Bites
With bites on the head or neck, the biggest initial concern is swelling, Kassouf says. Significant swelling from an allergic or inflammatory reaction could potentially compromise the airway or other functions of vital structures of the face, she explains.
[See: 6 Health Hazards to Watch Out for This Summer Other Than Skin Cancer.]
Spider Bite Treatments
If you are bitten by a spider, wash the site with soap and water. A cool compress can ease swelling, and an over-the-counter pain medicine such as Advil, Aleve or Tylenol can relieve pain.
Most bites just go away, Kassouf says. If itching and discomfort persist, topical steroid creams can help, she says. If bite discomfort keeps you up at night, she says, oral antihistamines or prescription steroid pills are options.
Murphy tends to tell patients to use Allegra, Zyrtec or Claritin for itchy bites because they’re less sedating than Benadryl. He also advises against topical Benadryl or other antihistamine creams, which can make rashes worse.
“If you scratch a lot and you open [the skin] up, then you might need a topical antibiotic so it doesn’t get infected,” Kassouf says. Scratching opens the door to staph and other infections. “That’s the main reason you don’t want to scratch too much,” she says.
Young children with suspected spider bites should be seen by a doctor.
[See: 11 Items That Help Protect Your Health.]
Spider Bite Prevention
The National Capital Poison Center website offers steps to lower spider-bite risks, such as shaking out gloves, boots, shoes, clothing and blankets before use, especially if they’ve been in storage.
Before entering basements, attics, unused closets and storage areas, make noise or vibrations. Cut clutter to eliminate nooks and crannies. Consider glue traps for your home, and contact a professional pest control operator if you suspect an infestation.
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How to Recognize and Treat Spider Bites originally appeared on usnews.com
Update 04/25/18: This article was originally published on July 8, 2016.
