Brown Recluse Spiders: What to Know

You may not feel anything at first. Within hours of the bite, you may feel mild burning or irritation in the bite wound. You may have any of the following:

Brown Recluse Spider Bite

Medically reviewed by Drugs.com. Last updated on Jan 5, 2023.

What do I need to know about a brown recluse spider bite?

Brown recluse spiders are venomous. The venom may cause severe skin and tissue damage after several hours or days.

What are the signs and symptoms of a brown recluse spider bite?

You may not feel anything at first. Within hours of the bite, you may feel mild burning or irritation in the bite wound. You may have any of the following:

• Severe swelling and pain at the site
• Blister that is blue in the center and ringed by redness
• Pimple-like lesion with yellow or green pus
• Ulceration (break in skin or mucous membrane)
• Rash that itches
• Dark urine
• Fever, chills, nausea and vomiting, or seizures
• Joint pain

How is a brown recluse spider bite diagnosed?

Your healthcare provider will ask about your symptoms and examine the injured area. He or she may ask about your medical history. You may need to have blood or urine tests or a skin biopsy. If you are able to capture the spider safely, bring it to your provider.

How is a brown recluse spider bite treated?

The bite wound may heal on its own, but you will need treatment if the wound gets worse. It is important to clean the wound site with soap and water. You may need any of the following:

• Medicines may be given to help prevent or treat pain, itching, or a bacterial infection. There is no antivenom available for a brown recluse spider bite. You may also need a booster vaccine called Td if it has been at least 10 years since your last dose. The Td vaccine helps prevent tetanus. Tetanus is a disease that can develop after a puncture wound.
• Surgery may be done if the damaged tissue around your wound becomes large and needs to be removed. Your healthcare provider will clean the area and remove dead tissues to help the wound heal faster.
• Hyperbaric oxygen therapy used to get more oxygen into your body. The oxygen is given under pressure to help it get into your tissues and blood. You may need to have this therapy more than 1 time.

How do I care for the bite area?

• Rest the area as directed to help your wound heal.
• Ice the wound. Ice helps decrease swelling and pain. Put ice in a plastic bag. Wrap the bag with a towel and put it on the site of the spider bite for 10 to 20 minutes.
• Compress the wound. A compression bandage around the wound can reduce pain and swelling.
• Elevate the wound. Keep the bite area above the level of your heart to help decrease redness and swelling. If you were bitten on the arm or leg, prop it on pillows to keep the area elevated comfortably.
• Wash your hands before and after you take care of your wound.
  
• Clean your wound with mild soap and water. Pat the area dry. Do not rub the wound. Clean your wound as often as directed by your healthcare provider. If you cannot reach the wound, have someone help you.
• Carefully check the wound and the area around it. Watch for more swelling, redness, or fluid oozing out. Apply gentle pressure to stop any bleeding.
• Cover your wound with a layer of sterile gauze bandage or other dressing as directed by your healthcare provider. If the bandage should be wrapped around your arm or leg, wrap it snugly but not too tight. It is too tight if you feel tingling or lose feeling in that area. Keep the bandage clean and dry.

How can a I prevent a brown recluse spider bite?

• Recognize the spider. Brown recluse spiders are usually brown and have a pattern on the back that looks like a violin.
• Learn where to find them. Brown recluse spiders live in the central and southern parts of the United States. They can be found from April to October and are active at night. They prefer to live in dark, warm, dry places. Some examples are under rocks, boards, and woodpiles, in dark corners, and under furniture.
• Use caution. Brown recluse spiders are not aggressive. They bite people only when threatened. Make noise when you enter attics or other spaces where spiders may live. Noise may scare them away. Use caution when you remove a web or spider.
• Be proactive. Clean closets, sheds, and attics completely. Shake out clothes or shoes that are lying on the floor or stored before you put them on. Check your sheets before you get into bed. Remove woodpiles and other trash from outside areas, especially piles where spiders can live. Wear gloves, long sleeved shirts, pants, and shoes when you work near wood or garbage piles.

Call your local emergency number (911 in the US) if:

• You have trouble talking, walking, or breathing.

When should I seek immediate care?

• You have a fever or chills.
• The skin around your wound gets red, or the wound gets more painful.
• You have a headache or nausea with vomiting.
• You have numbness or tingling in the bite area.
• Your urine is darker, or you urinate less than is usual for you.
• Your wound does not stop bleeding even after you apply pressure.
• Your wound or bandage has pus or a bad smell.

When should I call my doctor?

• You have a rash, itching, or swelling after you take your medicine.
• The bite becomes red and swollen.
• You have pain or problems moving the injured part or get tender lumps in the groin or armpits.
• Your wound continues to get larger.
• You have questions or concerns about your condition or care.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© Copyright Merative 2022 Information is for End User’s use only and may not be sold, redistributed or otherwise used for commercial purposes.

Learn more about Brown Recluse Spider Bite

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Brown Recluse Spiders: What to Know

It’s rare for someone to stumble upon a brown recluse spider, because these eight-legged creatures are true to their name: They prefer to be left alone. They tend to live in indoor and outdoor spaces where people don’t go most of the time. If you do find yourself in the same place as one, though, it won’t want to attack you — it’ll want to get out of your way. But if it feels trapped, it may bite you.

Brown recluse spiders are one of two spiders found in the United States that can cause real trouble if they bite you. They produce harmful venom that may cause a painful sore at the site of the bite. It may cause even more severe symptoms in some people. If you have a run-in with a brown recluse, it’s wise to have a doctor check you out, just in case.

What Does It Look Like?

A brown recluse might not be brown, but tan. It has a violin-shaped area on the front half of its body, with the neck of the violin pointing toward the spider’s abdomen.

It may be bigger than other spiders that you’re used to seeing. Its body can range in size from a quarter-inch to three-quarters of an inch, and its long legs make it appear even larger.

Most spiders have eight eyes, but a brown recluse spider has six. Two are in the front, and there are two more on each side of its head.

Brown recluses are found mostly in the Midwest or the South. The spider favors indoor spaces, like attics, garages or dark closets. Outdoors, it hides in out-of-the-way places — under logs, beneath porches, or within piles of rocks.

Symptoms of a Brown Recluse Bite

A bite might not hurt at first or even leave a mark. For some people, it feels like a pinch or a bee sting.

Within the first day or two after you’ve been bitten, you may notice:

• Pain or redness at the site of the bite
• A deep sore (ulcer) that forms where you were bitten, with the skin at the center turning purple
• Fever
• Chills
• Nausea
• Joint pain
• Feeling weak
• Seizures or coma (very rare)

Diagnosis

Your doctor will want to be as certain as they can that you were, in fact, bitten by a spider. It’ll help if you can describe what the spider looked like. Some people try to catch the bug to show the doctor. That’s fine, as long as you can do it safely. You might just try to take a photo of it.

Treatment

If you suspect your small child was bitten by a brown recluse, see your doctor right away. Their bodies can’t ward off the dangerous effects of the spider’s venom.

For adults, most brown recluse spider bites can be treated at home with good results. But about 10% of them cause ulcers or blisters that damage your skin so badly that you need a doctor’s care.

If your symptoms are mild, try these simple home remedies:

• Clean it with soap and water.
• Apply antibiotic cream.
• If you were bitten on an arm or leg, keep it raised while you’re resting. This can reduce swelling.
• Put ice on it.
• Take over-the-counter pain medicine.
• Watch for more severe symptoms.

See a doctor right away if you notice any of these symptoms:

• The bite has formed an ulcer or blister with a dark (blue, purple or black) center.
• You’re in extreme pain.
• You have an infection at the site of the bite.
• You’re having trouble breathing.

Some spider bites can have tetanus spores, so you might need a tetanus shot after you’ve been bitten. If you have an infection, you may need antibiotics.

Show Sources

U.S. Department of Labor: “Brown Recluse Spider.”

CDC: “Venomous Spiders,” “Types of Venomous Spiders.”

Mayo Clinic: “Spider Bites Overview,” “Spider Bites Diagnosis,” “Spider Bites Symptoms and Causes,” Spider Bites: Preparing for Your Appointment,” “Spider Bites Treatment.”

Nemours Foundation: “Bug Bites and Stings.”

University of California: “Brown Recluse and Other Recluse Spiders.”