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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

Open pop-up dialog box Close Black widow spider Black widow spider The black widow spider is known for the red hourglass marking on its belly.

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

Brown recluse spider

Open pop-up dialog box Close Brown recluse spider Brown recluse spider The brown recluse spider is known for the violin-shaped marking on its top.

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



