A bite from a brown recluse spider, or Loxosceles reclusa, can be mild or severe and may require medical attention. The toxins from this spider’s bite can cause tissue death.
Bites from the brown recluse spider almost never result in death but can cause serious skin damage, nausea, and muscle pain. With proper care, mild bites resolve within days to weeks, while more severe cases can take months to heal.
A bite from the brown recluse spider requires first aid, and, if necessary, professional medical attention. Treatment often includes cleaning the affected skin, pain relievers, and icing.
Keep reading to learn the symptoms and stages of a brown recluse spider bite, how to identify the spider, and when to seek help.
What’s in the bite?
Even though this spider’s size maxes out at about a half-inch (“), the venom of the brown recluse spider is more toxic than that of a rattlesnake. However, the brown recluse is only capable of releasing a little into our system.
Here are two key toxins in the venom:
- Sphingomyelinase D: This has the potential to destroy skin tissues.
- Hyaluronidase: This can speed the venom’s penetration into tissue.
View the slideshow below for photos of brown recluse spider bites.
A brown recluse’s venom can destroy blood vessels, tissue, and nerves. As a result, the skin tissue can die, a phenomenon called skin necrosis.
In a
Prompt treatment can slow these effects and allow your skin to begin healing faster.
Initial symptoms
Brown recluses have very small fangs, and their bite is usually initially painless. Unless you saw it happen, you might not initially be aware that a spider has bitten you.
You may start to notice a stinging sensation after around
The bite may appear as two tiny puncture holes. Early on, its center will be a pale color, with an inflamed outer ring.
Within 2 to 3 days
In some people, the brown recluse’s venom is localized to only the area where the spider bit you.
But for others, the venom spreads. This causes the wound to expand, usually over a period of around 2 to 3 days.
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
Within 1 to 2 weeks
Ulceration may develop within 1 to 2 weeks after the bite.
For mild bites, you should be mostly healed by a few weeks or see a drastic reduction in inflammation.
If you have a more severe bite, the spider’s toxin will continue to break down the skin, especially if you do not receive treatment. The site of the wound may start to develop necrotic (dead) tissue called eschar, though this may develop earlier. It looks like a big, black scab covering the wound area.
Within 3 months
Most brown recluse bites will heal fully within 3 months.
In some cases, where a lot of venom was delivered, necrosis in the wound can extend beyond the skin and into the muscles. If tissue death continues to occur or has already affected a large area, you’ll need to be evaluated by a surgeon. Surgery may be required to remove or repair excess dead tissue.
If the wound hasn’t responded to treatment or if symptoms don’t align with the typical presentation of a brown recluse bite, it may be time for a differential diagnosis. Your symptoms could be due to a bite or sting from a different spider or insect.
Severe reactions to a brown recluse spider bite
Some people have severe or life threatening reactions to brown recluse bites.
Severe reactions to a brown recluse bite can include the following symptoms:
- chills
- fever
- nausea
- weakness
- joint pain
- seizures
If you or a loved one is experiencing the above symptoms, seek emergency medical assistance. This may be a sign of anaphylactic shock, a life threatening allergic reaction.
Anaphylaxis is a severe reaction to a trigger, such as an allergy, and is potentially life threatening.
Symptoms can develop quickly and include:
- feeling faint or lightheaded
- difficulty breathing or wheezing
- rapid heartbeat
- confusion
- anxiety
- clammy skin
- collapsing or losing consciousness
- hives
- swelling
- stomach pain, nausea, or vomiting
If you or someone nearby develops these symptoms, you should:
- Check to see whether they have an epinephrine pen. If they do, read and follow the instructions to dispense the medication.
- Dial 911 (or a local emergency number).
- Lay them down. If they have vomited, lay them on their side.
- Stay with them until emergency services arrive.
It is possible for someone to need more than one injection with an epinephrine pen. If symptoms do not begin to clear after 5 minutes, give a second injection if one is available.
Learn more about identifying spider bites.
Recognizing the appearance of a brown recluse spider can help with identifying what has bitten you. View the slideshow below for photos of brown recluse spiders.
The brown recluse spider is usually no larger than a half-inch (“) in length, including its eight thin legs. It has a plain tan or brown color, with no stripes or patterning.
Adults almost always have a dark “violin-shaped” mark on their heads. For this reason, the brown recluse is sometimes called the “violin spider” or “fiddleback spider.”
Brown recluses have six eyes instead of the usual eight. These eyes are arranged in a horizontal row of 3 pairs on the face.
If you see a brown recluse or signs of them, like when they “shed” their skins, collect evidence if safe to do so, such as by taking a picture of the spider. This could help a doctor determine if a brown recluse bit you, and if you need medical treatment.
If bitten, it’s important to:
- avoid touching or scratching the bite
- clean the affected area with soap and water
- apply a fresh, non-stick bandage
Do not attempt to extract the spider’s venom. While first-aid procedures for several types of bites and stings involve trying to extract poison or venom,
Not all bites require medical treatment, and some can be treated at home. Keep close tabs on the bite. If it causes acute burning and pain or is getting worse instead of better after a few days, contact a doctor right away.
There is no specific treatment for a brown recluse spider bite. To manage symptoms, your doctor may recommend:
- keeping the area clean with soap and water
- covering the area with a clean non-stick bandage
- avoiding touching or scratching the bite area
- taking antihistamines to reduce itchiness
- taking antibiotics if an infection develops
Seeking treatment as soon as possible may help reduce the need for more invasive treatments.
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Brown recluse spider bites can be difficult to diagnose.
The bite can resemble a lot of other medical conditions,
- other insect bites
- deep fungal infections
- Stevens-Johnson syndrome
- cutaneous anthrax
- toxic epidermal necrolysis
- pyoderma gangrenosum, a condition that causes skin lesions
Geographical location is an important consideration when considering a potential brown recluse bite. If you don’t live in or haven’t traveled to a place where brown recluse spiders live, then your bite is probably due to something else.
The “NOT RECLUSE” diagnostic criteria
Some doctors may use the mnemonic NOT RECLUSE to determine if the bite could or couldn’t be from a brown recluse. This can help you (and them) remember the criteria for which the spider’s bite is judged.
The bite usually isn’t from 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 September.
- 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 2.5″ (10 centimeters) 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.
“Recluse” is an appropriate term for describing these shy spiders, which avoid light and hide in dark crevices. Brown recluse spiders aren’t aggressive by nature and will only bite if feeling threatened or trapped.
Ways you can try to avoid brown recluse bites include:
- reducing clutter in your home wherever possible, including removing any piles of newspapers, wood, or cardboard boxes
- keep shoes and clothes off the floor, and shaking out your footwear before wearing to ensure spiders aren’t in them
- storing items in air-tight plastic containers to stop spiders from getting into them
- wearing long sleeves and gloves while sorting through old materials, such as boxes in an attic
- ensuring cracks and holes in your home’s foundation and structure are properly sealed
- using sticky traps to capture spiders
Professional exterminators can also help you get rid of these and other pests that may cause bites and stings.
The information below provides some information about the brown recluse spider’s distinguishing features and where to find them.
| Regions found | These spiders typically live in the south-central portion of the United States, including Texas, Iowa, Ohio, Nebraska, and Georgia. It’s rare but possible that the spider gets accidentally transported outside its region. |
| When they appear | Brown recluses go into “harborages” for the winter, which is any hidden area the spider can find shelter in. They emerge between April and May, usually going away around October. |
| Where they live | These spiders look for warm crevices to crawl under, such as insulation, cardboard boxes, and 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 do spin webs, but they don’t use them to trap their prey. Instead, they use the web as a home or refuge. They eat crawling bugs, like cockroaches, ants, and crickets. |
| Lifespan | Brown recluses live long lives, sometimes up to 3 to 5 years. |
Because of their size and brown-ish appearance, the wolf spider is often mistaken for the brown recluse.
The wolf spider is not venomous to humans though they can still bite. You’ll need to clean and treat the bite to prevent it from becoming infected and watch out for signs of an allergic reaction.
Here’s a breakdown of major differences between these two arachnids:
| Brown recluse spider | Wolf spider |
| No larger than 1/2″ in size | 1/4″ to 2″ in size |
| Venomous bite, considered very dangerous to humans | Venomous bite, not considered dangerous to humans |
| plain tan or brown, with violin-shaped dark mark on head, covered in thin hairs | gray with dark brown or gray markings on body and legs, slightly furrier appearance than brown recluse |
| spins webs, hunts on ground | doesn’t spin webs, hunts on ground |
| 6 eyes | 8 eyes |
Brown recluse spider bites are often painful and can cause skin tissue to die. It may take several hours to notice that you’ve been bitten. It can take weeks or months to fully heal
Implementing first aid can help reduce symptoms. Clean the skin with soap and water, and use a non-stick bandage. OTC pain medications can help with discomfort.
Avoid itching the bite and do not attempt to extract venom.
With proper care at home, most brown recluse bites will heal on their own over the course of several weeks. If your bite is especially painful or skin inflammation is spreading, contact your doctor for evaluation and further treatment.