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Black Widow Spider Bite

Black Widow Spider Bite Overview

Picture of Black Widow Spider Bites Most people avoid spiders. Many fear them. Scary movies use spiders to create creepy, crawly suspense. The bite of a black widow spider sounds serious-and it can be-but the creepy part is that you may not realize you have been bitten until you become ill.

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 with their bites.

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. Two species are common to the United States.

    • 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 2 crosswise bars on the undersurface. Just to make things interesting, the markings can also be yellow or white, and the spider itself may be brown or have red legs.

  • 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.

 

Black Widow Spider Bite Symptoms

The black widow spider produces a protein venom that affects the victim's nervous system. Some people are slightly affected by the venom, but others may have a severe response. The first symptom is acute pain at the site of the bite though there may only be a minimal local reaction.

 

  • The local pain may be followed by localized or generalized severe muscle cramps, abdominal pain, weakness, and tremor. In severe cases, nausea, vomiting, faintness, dizziness, chest pain, and respiratory difficulties may follow.

  • The severity of the reaction can depend on the age and physical condition of the person bitten. Children and the elderly are more seriously affected than young adults.

  • In some cases, abdominal pain may mimic such conditions as appendicitis or gallbladder problems. Chest pain may be mistaken for a heart attack.

  • Blood pressure and heart rate may be elevated.

  • People rarely die from a black widow's bite. Life-threatening reactions are generally seen only in small children and the elderly.

When to Seek Medical Care

In general, treatment for serious reactions to a black widow spider's bite will be beyond the scope of most medical offices and urgent care centers. Pain relief may require the use of narcotics and antivenin (antitoxin to counteract the effects of the spider venom).

The decision to seek emergency care is usually easy and should be made early. If the person who was bitten by a black widow spider has more than minor pain or has whole-body symptoms, seek care at a hospital's Emergency Department. If symptoms are severe, call 911 for emergency medical transport so that evaluation and treatment can start en route to the hospital.

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WebMD Medical Reference from eMedicineHealth

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