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4) Pitts RM, Callahan M, Owings E, and King W: Tough Spiders: Identifying and
treating their bites. The Children's Hospital of Alabama, Poison Information Bulletin,
Southeast Child Safety Institute. Vol 21, No 1, Oct. 1992.
C. Scorpion Stings: Approximately 650 species of scorpions inhabit the world, mainly
distributed in tropical and subtropical areas. An estimated 40 of these species live in the
United States, distributed across 75% of the country but concentrated in the warmer
regions. All scorpions inject venom through a single sharp stinger at the tip of the "tail,"
which is actually an extension of the abdomen. Contact with scorpions is usually
accidental. They feed at night. During the daytime they may take shelter in clothing,
boots, and bedding. Outdoors, they may often be found under rocks and logs. Checking
their hiding places in known scorpion areas is good advice for any traveler. Although the
sting is painful, few species inject sufficient venom to be of concern to humans. The only
potentially lethal U.S. scorpion is Centruroides exilicauda (or sculpturatus). C. gertschi
is generally considered a variety of sculpturatus. This scorpion is found in the Southwest,
primarily in Arizona. It is most active May through August, hibernating in winter. Since
specific identification is difficult, the traveler is advised to inquire locally about what
dangerous species are present before traveling into scorpion territory. As with black
widow spiders, most deaths and serious reactions from Centruroides stings are in small
children, the elderly, and hypertensives.
Any sting typically produces a burning pain, minimal swelling, redness, vesicles,
numbness, tingling, and, uncommonly, weakness or numbness of the affected extremity.
Centruroides stings are usually acutely painful, with a hypersensitive zone soon
developing around the site. The injured area may be sensitive to touch, pressure, heat, and
cold. Salivation, diaphoresis, perioral paresthesias, dysphagia, gastric distention,
hyperactivity, diplopia, nystagmus, visual loss, incontinence, penile erection, exaggerated
reflexes, abdominal pain, opisthotonos, seizures, hypertension (more common),
hypotension (less common), pulmonary edema, coma, and muscle paralysis (including
respiratory paralysis) can ensue, especially in children. Most non-lethal symptoms last
less than four hours.
Treatment includes evaluation and application of cold to the sting site. Clean the
site and apply a sterile, or at least clean, dressing. For severe pain, splint or immobilize
the affected extremity. Oral, non-narcotic analgesics may be useful. If serious symptoms
develop (see above), immediate evacuation is indicated. If possible, bring the scorpion
along on the evacuation, but avoid direct handling.
For those with the skill and equipment, benzodiazepine or phenobarbital may be
used for seizures and excitability. Methocarbamol may be administered IV for severe
muscle spasms. Oral or parenteral antihypertensive medications (such as clonidine) may
be required. If there are profound cholinergic effects, administer atropine. Give IV fluids
carefully, if needed, since pulmonary edema may develop. Observe all healthy adults for
at least four hours after a sting. Admit to the hospital all children and elderly patients
stung by scorpions.
Administer IV antivenin only in cases of severe poisoning. It is available in most
areas where dangerous scorpions exist. In the United States, it is only available in
