Spiders: Terrible houseguests but not frequent biters

Feeling the creepy crawlies lately? That might be because spider activity can surge during the hot summer months, and you may be seeing more of the eight-legged arachnids around your home.

Whether seeking cooler areas, food sources or potential mates, spiders often find their way into homes — and onto the people inside. They might even take a bite out of you or your loved ones.

While spiders only bite humans in self-defense when accidentally trapped, touched or startled — not because they find you tasty or nutritious — certain bites can lead to discomfort or pain, even paralysis.

“Most spiders are harmless and tend to avoid people, so serious bites are less common than many people think,” says Dr. Amy Zheng, an urgent care physician with Sharp Rees-Stealy Medical Group. “In my 25 years practicing in emergency medicine, truly serious spider bites have been extremely rare.”

However, some venomous spider bites can be troublesome.

Spider bites you’ll want to avoid

According to the County of San Diego, venomous spiders in the region are rare but include the adult female black widow, brown widow and the desert recluse spiders. A bite from one of them requires immediate medical attention, so it’s essential to know how to identify them.

• Black widow: The female’s abdomen is shiny, black and round with a red hourglass figure on the underside. Adult females are about 1/2-inch long, not including the legs. Their egg cases are smooth.

• Brown widow: These spiders are mottled tan and brown in appearance. They have an orange hourglass figure on the undersides of their abdomens. Their egg cases are bumpy.

• Desert recluse: This small, sandy-tan to light-brown spider is about 1/4- to 1/2-inch in size with a leg span up to 1 inch. It has six eyes arranged in pairs, a solid-colored abdomen and a faint violin-shaped mark on its back.

“Black widow bites can cause symptoms such as muscle pain, abdominal pain and headaches, while brown recluse bites tend to cause more localized skin reactions with redness, blistering and a burning sensation,” Dr. Zheng says.

Certain people, such as children under 6, people over 60 and those with heart disease, are at greater risk of a dangerous reaction to these spiders’ bites.

Caring for a spider bite

Most spider bites are harmless and might cause mild redness, itchiness and swelling that will last for a few days, as long as they don’t become infected. The County recommends avoiding scratching, washing a spider’s bite mark with soap and water, and rubbing ice cubes on the bite to numb and reduce the pain. Over-the-counter antihistamines (such as Claritin, Benadryl, Zyrtec or Allegra) can also be taken, if needed.

“If you experience expanding redness, drainage, fever, increasing pain, tingling or a soft, swollen area that feels like a water balloon, seek medical care at an urgent care center or emergency department for evaluation,” Dr. Zheng advises.

Staying clear of spider bites

There are a few steps you can take to keep spiders out of your home and avoid being bitten.

The County of San Diego suggests:

• Sealing cracks on your house’s foundation and around windows and doors

• Using a high-pressure hose to spray spiders on outside walls.

• Ensuring you don’t carry spiders into your home on plants and in boxes

• Vacuuming or sweeping spiders and their webs from windows, corners of rooms, storage areas, garages and basements

• Cleaning up woodpiles and leaves around your home

• Spraying insecticide (follow the label instructions carefully)

Experts also agree it’s essential to wear shoes outdoors; avoid reaching into holes, under furniture or in woodpiles; and shake out clothing, towels, and shoes or boots before wearing them. You should also use caution around outdoor buildings and facilities, such as toilets, storage sheds, carports and greenhouses, which are favorite places for spiders to hide.

Talk with your doctor if you’re concerned about a reaction to a possible spider bite. Most “spider bites,” research has found, are more likely to be bites or stings from other insects, such as fleas or bedbugs, or skin infections, and your doctor can help determine the best treatment.

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