By Mayo Clinic Staff
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.
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.
- Use over-the-counter medications. Try a pain reliever, such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others), or an antihistamine (Benadryl, Chlor-Trimeton, others).
When to seek medical care
Seek prompt medical attention in the following situations:
- You are unsure whether the bite was from a poisonous spider.
- The person who was bitten experiences severe pain, abdominal cramping or a growing ulcer at the bite site.
- The person who was bitten isn't breathing.
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. The bite feels like a pinprick. You may not even know you've been bitten. 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
- Excessive sweating
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:
Feb. 07, 2015
- At first, a mild stinging
- Redness and intense pain, within eight hours
- A deep blue or purple area around the bite, which may develop a red ring around it
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