Wolf Spider Bite

A wolf spider bite hurts like a bee sting and causes a red, swollen bump, but it isn't dangerous: wolf spider venom is not considered medically significant to people. Clean it, apply a cold pack, and expect it to settle within about a day; watch for signs of infection or allergy.

Are wolf spiders poisonous or venomous?

Strictly speaking, wolf spiders are venomous, not poisonous: they inject venom through their fangs to paralyze prey. Almost every spider is venomous in this sense, and as the Burke Museum's arachnologists put it, no spider is known to be poisonous to eat. What matters is whether the venom harms people, and wolf spider venom causes nothing beyond local pain, redness and swelling. The Burke Museum lists wolf spiders among spiders "falsely accused" of causing serious bites.

Do wolf spiders bite?

Rarely. Wolf spiders (full profile) run from people. Penn State Extension notes bites happen mainly when a spider is mishandled or pinned against skin, for example when someone:

• picks one up or tries to brush it off bare skin;
• steps on one barefoot at night;
• traps one in a shoe, glove, bedding or clothing;
• handles a female carrying an egg sac or spiderlings, when they're most defensive.

Large species such as the Carolina wolf spider have fangs strong enough to break skin; many small ones can't.

What does a wolf spider bite look like?

• a red, raised bump, usually under 1 inch across;
• sometimes two tiny puncture marks in the center (often too small to see);
• mild swelling and itching around it;
• in some people, redness spreading an inch or two.

Wolf spider bite pictures online often show infected wounds or other conditions mislabeled as spider bites. A real wolf spider bite doesn't turn black, form an ulcer, or rot.

Wolf spider bite symptoms and stages

Occasionally people notice tender lymph nodes near the bite. Severe pain spreading through the body with cramping and sweating is not typical of a wolf spider and suggests a black widow bite instead.

Wolf spider venom

Wolf spider venom is built for insects and small prey. Older claims that wolf spiders caused necrotic, flesh-eating wounds were traced to misidentified spiders or to infections. Penn State notes no serious medical consequences have been recorded.

Was it really a wolf spider?

Often not. In spider-ID communities, a large share of "wolf spider bite" posts turn out to involve other spiders: a cross orb weaver on a fence, a funnel weaver in a garage, a ground spider. That's reassuring, since nearly all of these are harmless too. Two situations deserve a second look:

• Recluse country (Missouri, Kansas, Oklahoma, Arkansas, Tennessee, Kentucky and neighbors): a smooth, plain tan spider with a violin mark and six eyes is a brown recluse, not a wolf spider. Wolf spiders are hairy and striped, with two big front eyes.
• Mystery bites in bed: a spider bite hurts enough to wake you. Several bites, or new ones every morning, almost always point to bed bugs, fleas, mosquitoes or a skin condition. In one r/pestcontrol thread, someone sure that house spiders were biting him nightly put out glue traps, caught just two spiders, and was told by several pros to check for bed bugs.

What people who dealt with it say

People who were actually bitten (usually after picking a wolf spider up or trapping one against their skin) describe a sharp sting and a sore red bump that was gone by the next day or two. The bigger problem in most threads is fear: someone finding one wolf spider a day in their bathroom or bed, for example. The practical advice from r/pestcontrol is consistent: keep bedding from touching the floor (wolf spiders are poor climbers), vacuum floors and edges, seal gaps under doors, and remember a spider in the bed is a wanderer, not a sign of an infestation. Pets that catch wolf spiders typically end up with nothing worse than a licked paw.

First aid

1. Wash the bite with soap and water.
2. Apply a cold pack wrapped in cloth for 10–15 minutes at a time.
3. Raise the area if it's on an arm or leg.
4. Use an over-the-counter pain reliever or antihistamine for itching if needed, following the package directions.
5. Keep it clean and don't scratch it open; scratched bites are what most often get infected.
6. If you're unsure what bit you, call Poison Control (1-800-222-1222) for free advice.

When to see a doctor

See a doctor if:

• redness keeps spreading after 24–48 hours, or the area becomes hot, more painful, or drains pus (signs of infection);
• red streaks run from the bite;
• you develop a fever;
• the bite darkens, blisters badly or forms an open sore, since it probably isn't a wolf spider bite;
• you have signs of allergy: hives, face or throat swelling, or trouble breathing. Call 911.

Wolf spider or brown recluse?

See brown recluse and brown recluse bite.

Preventing bites

Wear shoes outdoors at night, shake out shoes and clothes left in garages, use gloves when moving firewood or rocks, and fit door sweeps so wanderers don't get in. If you need to move a wolf spider, use a cup and a piece of card instead of your hand. For more, see how to get rid of spiders.