Black Widow Spider Bite
- Black Widow Spider Bite Overview
- Black Widow Spider Bite Symptoms
- When to Seek Medical Care
- Black Widow Spider Bite Treatment
- Self-Care at Home
- Medical Treatment
- Medications
- Next Steps
- Follow-up
- Prevention
- Outlook
- Synonyms and Keywords
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Black Widow Spider Bite Overview
Of the 30,000 types of spiders, the black widow is probably the one best known and feared. Although spiders are often blamed for all kinds of symptoms, from local itching to diffuse rashes, the fact is that spiders rarely bite humans, and in fact, most spider bites do not even break the skin.
The bites of very large spiders such as tarantulas can be painful. Otherwise, in the temperate regions, the only spiders to be feared are the black widow and the brown recluse.
- The black widow is a medium-sized spider whose body is about a half-inch long. The name is derived from the mistaken belief that the female invariably kills the male after mating. Although the spider is mostly found in the southern
United States, it may be seen throughout the US. Five species are common to the US, with two of them being the most common:
- The southern black widow has the shiny, black, globular abdomen with the distinctive red hourglass on the underside.
- The northern black widow has a row of red spots down the middle of the upper surface of its abdomen and two crosswise bars on the undersurface. The markings can also be yellow or white, and the spider itself may be brown or have red legs.
- The southern black widow has the shiny, black, globular abdomen with the distinctive red hourglass on the underside.
- Black widow spiders are nocturnal and, thus, are active at night. They prefer dark corners or crevices. They are said to avoid human dwellings, but you can find them in such areas as outhouses and garages. Only the female black widow bites humans, and she bites only when disturbed, especially while protecting her eggs.
Picture of the underside of a black widow spider and an egg sack
Picture of a top view of a black widow spider
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Black Widow Spider Bite
Wilderness: Black Widow and Brown Recluse Spider Bite »
Spider Bite Overview
Black widow spiders (Latrodectus mactans) may be black or brown with a leg span of approximately one to two inches. Most can be identified by a red hourglass marking on the abdomen. They are located throughout the United States. Their toxin causes nerve cell dysfunction and muscle cell twitching.
Brown recluse spiders (Loxosceles reclusa) are tan to dark brown with a leg span of approximately 1 inch. Many have a violin-shaped marking on the chest. They are located mainly in the south central United States.
Both species are common in North America and throughout the world. Human contact with these spiders is usually accidental.
Spider Bite Symptoms
Black widow a spider bites result in a halo lesion consisting of a pale circular area surrounded by a ring of redness.
- The initial bite of the black widow spider is usually painful, and the vi...
Read the Wilderness: Black Widow and Brown Recluse Spider Bite article »
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Spider Envenomation, Widow »
Widow spiders belong to the genus Latrodectus and include the black widow spider (Latrodectus mactans mactans) in the United States.
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