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Spider Bite Symptoms


Spider bites are a very common occurrence. There are 2 spiders, though, that warrant concern, the black widow spider and the brown recluse spider.

The black widow spider

The black widow spider is found throughout the US, although it is more commonly seen in the South. It is glossy black with bright red or orange markings on the under surface of its belly. The species L mactans has the classic hourglass markings. Its body is about ¾ of an inch in length, with legs about 3 inches long. The black widow likes to live under rocks, in woodpiles, and in outhouses or stables. The bite feels like a pinprick, and appears pale with a red border. In about an hour, the site becomes painful. Soon after, whole body symptoms appear including severe muscle cramping, agitation, a board-like belly, nausea, vomiting and high blood pressure. If no treatment is given at all, all symptoms will resolve in 24 to 48 hours. If pain and agitation are severe, pain relievers and anxiety reducing medications will be given in the emergency room. Every case will not receive antivenin. Antivenin is reserved for those with severe symptoms.

The brown recluse spider

The brown recluse spider, also known as the fiddleback spider, is so called because of its distinctive brown violin-shaped marking on its chest. The body of this spider is small–about ½ inch long with legs 2 inches long. This spider likes dark, undisturbed places such as woodpiles, closets, and basements. It is most commonly seen in the river country of mid-America and in the South. The bite may go unnoticed, or feel like a pinprick. Within 2 hours, the site is painful and appears bluish in color. Soon after, symptoms appear that include fever, chills, nausea, and vomiting. As with black widow spider bites, the treatment is mainly supportive, with control of pain as the main objective. After 1 to 2 days, a blister will form at the site of the bite that will eventually form an ulcer. It will take several weeks for this ulcer to heal.