Brown Recluse Spider Bite
What is a brown recluse spider?
The brown recluse spider is an eight-legged arachnid that is tan to dark brown in color, with a violin marking on its back that can range anywhere from 1/4 inch to 1/2 inch long. Younger spiders or those that have just molted won’t have the violin marking.
Where does a brown recluse spider live?
Brown recluse spiders can be found in the southeastern and midwestern U.S. The brown recluse spider prefers to live in warm, dry and dark places.
Outdoors, brown recluse spiders can be found near rocks, utility boxes, near woodpiles and under bark.
Indoors, brown recluse spiders could live in any area that has not been disturbed. They can be found in boxes, in unworn clothing and shoes, in corners of a home and in crevices such as in an attic, crawl space, basement or closet.
Who do brown recluse bites affect?
The brown recluse spider is not aggressive but will bite anyone if it feels threatened. Children, the elderly and those with preexisting medical conditions are most likely to have a severe reaction to the bite.
How common is a brown recluse spider bite?
Almost all spiders have the ability to bite, but the fangs of most spiders are too small to penetrate human skin. Spider bites, including bites by the brown recluse, cause only a few deaths per year in the U.S., usually in children.
How does a brown recluse bite affect my body?
Brown recluse bites can cause redness, itchiness, pain and wounds. If the wound is untreated, it could lead to bruising, a blister, an open sore and scarring.
Symptoms and Causes
What would cause a brown recluse spider to bite?
A brown recluse could bite you if you disturb its home. Though the spider will not pursue a person, if you come in close contact with a brown recluse, it may bite to defend itself. Spiders like to hide in dark spots like beds and clothing. Spider bites tend to occur indoors when you unknowingly come into contact with it.
What happens when a brown recluse bites you?
A bite from a brown recluse spider will not be instantly noticed because its bite is painless. Bite reactions vary from mild irritation to a potentially dangerous reaction.
What are the symptoms of a brown recluse bite?
- Ache at the site.
- Pain surrounding muscles near the bite.
- Pain in your abdomen, back, chest and legs.
- Blister at the site.
What are severe symptoms of a brown recluse bite?
- Restlessness or difficulty sleeping.
If you experience any severe symptoms, seek medical attention immediately.
What are the stages of a brown recluse spider bite?
Hours after a bite
- The area of the bite becomes sensitive and red about three to eight hours after the bite.
- The bite site feels like it is burning.
- The bite site changes color. It can have a bullseye look or can bruise and have a blueish color.
Three to 5 days after a bite
- If the spider injected a small amount of venom, immediate discomfort should disappear.
- If the venom spread beyond the bite area, discomfort could continue for several days and an ulcer would appear on the bite site.
Seven to 14 days after a bite
- In severe cases, the skin around the ulcer breaks down and becomes a wound that could take several months to heal completely.
Three weeks after a bite
- The majority of bites will heal after three weeks.
- A thick, black scab will cover the wound.
Diagnosis and Tests
How is a brown recluse bite diagnosed?
It can be difficult to identify a brown recluse bite unless you saw the spider bite you, especially since the brown recluse’s bite cannot be felt until hours after the bite occurred.
If you suspect you have been bitten, call a healthcare professional or visit the emergency room and bring the spider for identification purposes, if possible.
Can my doctor test for a brown recluse spider bite?
There is no test available to identify a brown recluse spider bite. But your healthcare provider may test for skin infections or other conditions based on the wound or blister as a result of the bite.
Management and Treatment
What are the effects of a brown recluse bite?
Brown recluse spider bites can cause wounds. If the wound is left untreated, the wound could result in an infection or scarring.
How do I manage symptoms of a brown recluse spider bite?
- Immediately clean the bite area with soap and water.
- Apply a damp cloth with cold water or ice to the bite area to reduce swelling.
- Elevate the bite area, if possible.
- Seek medical attention for severe symptoms.
- A healthcare provider may prescribe antibiotics to prevent infection.
How soon after treatment for a brown recluse bite will I feel better?
The majority of brown recluse bites will heal after three weeks if the bite is not severe. Seeking treatment at the first sign of a brown recluse bite will ease recovery time.
What happens if a brown recluse bite goes untreated?
If the area around the bite continues to grow and your pain increases, the wound may be infected, especially if the wound begins to drain a cloudy liquid. Infections could be dangerous and spread further from the wound. In serious cases, an untreated and infected wound could be life-threatening.
How can I reduce my risk of being bitten by a brown recluse?
Awareness and understanding where brown recluse spiders live are the first steps in reducing your risk of a bite. However, brown recluse spiders frequently go unnoticed due to their habitat and sneaky nature.
How can I prevent brown recluse spider bites?
There are steps you can take to prevent bites from a brown recluse spider. These include:
- Stop spiders from entering your home by sealing small openings with caulk.
- Remove spider webs from homes.
- Keep firewood at least 20 feet away from your home.
- Wear gloves when moving wood.
- Wear long sleeves and pants in areas with spiders.
- Shake clothing and shoes before wearing.
- Contact a pest control professional if you notice your home has a brown recluse spider infestation.
Outlook / Prognosis
What can I expect if I am bitten by a brown recluse spider?
If you are bitten, you can expect the following:
What it feels like
There may be delayed pain after the bite occurs.
What it looks like
- A blister.
- Swelling at the site.
- An ulcer (wound).
With proper care, most people will recover from a brown recluse spider bite.
When should I call the doctor about a brown recluse bite?
Call your doctor or visit the emergency room immediately if you experience any of the following:
- Your wound looks like it’s infected. It may be red, swollen, drain cloudy fluid or be painful to the touch.
What questions should I ask my doctor about a brown recluse spider bite?
- How do I treat my symptoms?
- What are the signs of infection?
- Am I at risk for any complications?
A note from Cleveland Clinic
Unfortunately, a bite from a brown recluse spider will not turn you into a comic book superhero. Discomfort from a bite is temporary and can be alleviated with quick treatment and proper wound care hygiene. If you live in an area with brown recluse spiders, take precautions in garages, basements and closets, and reach out to a pest control specialist if you feel that there is an infestation.
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