While no one wants to be bitten by a spider, you really don’t want a brown recluse to bite you. These spiders contain a rare toxin called sphingomyelinase D, which has the potential to destroy skin tissues.
Let’s put it this way: A brown recluse’s bite is more potent than that of a rattlesnake.
Keep reading to learn the symptoms and stages of a brown recluse spider bite.
A brown recluse’s venom can destroy blood vessels, tissue, and nerves. The venom destroys blood vessels, which causes ischemia or a lack of oxygen and blood flow to the tissue. As a result, the skin tissue dies.
Brown recluses have very small fangs, and their bite is usually painless. You may start to notice a red, tender, and inflamed area about 3 to 8 hours after the spider bit you. Over the course of several hours, the irritation may cause a burning sensation.
Some people will develop a necrotic lesion due to the spider’s bite. This may look like the following:
- dry, sinking patch of skin
- bluish-appearing patch of skin
- redness around the lesion with a pale center
- central blister
After 3 to 5 days
In some people, the brown recluse’s venom is localized to only the area where the spider bit you. If the spider injected minimal venom and you’re healthy, the discomfort usually goes away in about 3 to 5 days.
In others, the venom spreads. This causes the wound to expand, usually over a period of several days to weeks.
After 7 to 14 days
In those with more severe bites, the spreading ulcer can grow by inches. It doesn’t usually break down skin until about 7 to 14 days after the bite occurs. A wound of this nature may last for several months.
3 weeks later
Most brown recluse spider bites take about 3 weeks to heal. For those with more severe bites, the site of the wound starts to develop necrotic (dead) tissue called eschar. This looks like a big, black, thick scab that covers the wound.
3 months later
Most brown recluse bites will heal within 3 months. If the bite hasn’t healed, it may not be a brown recluse bite after all.
Some people have severe reactions to brown recluse bites. Severe reactions are more likely in those with compromised immune systems, like children and older adults.
Severe reactions to a brown recluse bite can include the following symptoms:
A person with these symptoms should seek emergency medical attention for supportive treatments.
If you see a brown recluse or even signs of them — like when they “shed” their skins — collect evidence. Even if you don’t have the spider, this could help a doctor determine if a brown recluse bit you, and if you need medical treatment.
Most doctors recommend using the rest, ice, compression, and elevation (RICE) method to initially treat a bite. Applying cloth-covered ice packs for 10 minutes at a time helps keep the spider’s venom from spreading.
Elevating the affected area and refraining from using it can help. Applying clean bandages to the area, especially when you are sleeping at night to reduce the urge to itch, can help.
Not all bites require medical treatment. If the bite causes severe burning and pain, or is getting worse instead of better after a few days, see a doctor.
Brown recluse spider bites can be hard to diagnose. The bite can resemble a lot of other medical conditions, including a Staph infection, pressure ulcers, and wounds due to diabetes. Other insect bites can look like a brown recluse bite, too.
Another consideration is where you live. If you don’t live or haven’t traveled to a place where brown recluse spiders live, then your bite is probably something else.
The spiders aren’t present in every part of the United States, so not all insect bites that look bad are brown recluse bites.
The NOT RECLUSE diagnosis
Some doctors may use the mnemonic NOT RECLUSE to determine if the bite could or couldn’t be from a brown recluse. The bite usually isn’t a brown recluse if it has the following characteristics:
- Numerous. A brown recluse usually only bites once — not multiple times.
- Occurrence. Brown recluses aren’t aggressive. Unless you’ve been in a place where they tend to hide or live, it’s not likely one bit you.
- Timing. Brown recluses only bite in months when they’re active —- usually from April to October.
- Red center. Brown recluse bites usually have a pale center with redness around the bite area.
- Elevated. Brown recluse bites are usually flat — if the area is elevated, it’s not likely a brown recluse bite.
- Chronic. A bite from a brown recluse will usually heal within 3 months.
- Large. A brown recluse bite is rarely larger than about 5 inches across. If the bite is larger, it could be from something else.
- Ulcerates too early. Most brown recluse spider bites won’t ulcerate until 1 to 2 weeks after the bite occurs.
- Swollen. Brown recluse spider bites don’t usually cause significant swelling unless they’re on the face or feet.
- Exudative. Brown recluse bites don’t usually leak or cause exudate (pus). They’re more blistering or scab-like in nature.
The way a doctor will treat a brown recluse bite may vary based on the location of the bite and your symptoms. Treatments may include:
- antibiotics to prevent infection
- special wound dressings or ointments to promote healing and reduce pain
- skin grafts or wound debridement to repair larger areas of damaged skin
Seeking treatment as soon as possible can help reduce the need for more invasive treatments.
“Recluse” is a great term to describe these spiders — they avoid light and hide in darker crevices most people don’t look at. For this reason, it’s hard to find areas of infestation. We don’t advise looking for them — it’s best to leave this to a professional.
Ways you can try to avoid brown recluse bites include:
- Reduce clutter in your home wherever possible. This includes no piles of newspapers or old cardboard boxes.
- Keep shoes and clothes off the floor. Shake out your shoes before wearing to ensure spiders aren’t in them.
- Store items in air-tight plastic containers. This stops spiders from getting into them.
- Wear long sleeves and gloves if you’re sorting through old materials, such as boxes in an attic. Spiders can’t usually bite through clothing, so this can offer some protection.
- Ensure cracks and holes in your home’s foundation and structure are properly sealed. Spiders can enter through these areas.
- Place flat glue traps in areas where spiders may live in your home. Examples include along baseboards where the wall and floor meet, as well as around areas of clutter.
Professional exterminators can also help you get rid of these and other pests.
|Appearance||Brown recluse spiders are tan to dark brown and about the size of a quarter. They have a distinct pattern of six eyes arranged in three, U-shaped pairs (most spiders have eight eyes). On their underside, they often have a darker marking that appears violin-shaped. This is why some people call the brown recluse a fiddleback or violin spider.|
|Regions found||They’re typically found in the south-central portion of the United States, including states like Texas, Iowa, Oklahoma, Tennessee, and Georgia. While it’s possible a person could transport a brown recluse outside its native region, it’s less likely.|
|When they appear||Brown recluses go into “harborages” for the winter and emerge in April to May, usually going away in around October.|
|Where they live||These spiders look for warm crevices to crawl under, such as insulation, cardboard boxes, or between pages of newspapers. Outdoors, they often live under the bark of dead trees or under rocks. They may crawl into shoes or bedding and bite you when they accidentally become wedged against your skin.|
|What they eat||Brown recluses aren’t aggressive. They do spin webs, but they don’t use them to trap their prey. Instead, the web is used as a home or refuge. They eat crawling bugs, like cockroaches, ants, and crickets.|
|Lifespan||Brown recluses live long lives, sometimes up to 5 to 7 years. They can go extremely long periods without eating, which is one of the reasons they live so long.|
Brown recluse spider bites are painful and sometimes highly damaging. If a bite does occur, most will heal on their own over the course of several weeks.
If your bite is especially painful or on a delicate area of the body, such as your face, see your doctor for suggested treatments.