Most spider bites cause only minor injury. A few spiders can be dangerous. In the United States, these include the black widow spider and the brown recluse spider.
Seek emergency care immediately if:
You were bitten by a black widow or brown recluse spider
You are unsure whether the bite was from a poisonous spider
You have severe pain, abdominal cramping or a growing ulcer at the bite site
The person who was bitten isn't breathing
To take care of a spider bite:
Clean the wound. Use mild soap and water and apply an antibiotic ointment.
Apply a cool compress. Use a cloth dampened with cold water or filled with ice. This helps reduce pain and swelling. If the bite is on an arm or leg, elevate it.
Take an over-the-counter pain medication if needed. If the wound is itchy, an antihistamine (Benadryl, Chlor-Trimeton, others) may help.
Your doctor may recommend a tetanus booster shot if you haven't had one in the last five years.
Black widow spider
You can usually identify a black widow spider by the hourglass marking on its belly. In the United States, this spider is more common in the South.
Signs and symptoms of a black widow spider bite may include:
At first, slight swelling and faint red marks
Intense pain and stiffness
Severe abdominal pain or cramping
Chills, fever and nausea
The black widow spider is known for the red hourglass marking on its belly.
Brown recluse spider
The brown recluse spider has a violin-shaped marking on its back, but this mark can be hard to see. In the United States, its range is central and southern states.
Signs and symptoms of a brown recluse spider bite vary but may include:
At first, a mild pain
Redness and intense pain
A deep blue or purple area around the bite, which may develop a red ring around it
The brown recluse spider is known for the violin-shaped marking on its top.
Last Updated Feb 14, 2018
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