Brown recluse spider bite: What are the potential effects?

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The brown recluse spider can cause medically severe bites. Even though all bites are painful, most settle on their own in a week. In some cases, severe complications might arise including coma and even death, but this is extremely rare.

The spiders have various hiding spots and due to this, they are mainly found indoors, usually in cupboards, basements, attics as well as inside and behind furniture. The spiders are not generally aggressive. On the other hand, if an unsuspecting individual roll over one while sleeping or wears a piece of clothing where the spider is hiding, the spider is faced with the possibility of being crushed, thus delivering a bite.

After 24 hours, a blister filled with fluid forms and bordered by an area of inflammation.

Immediate and immediate effects

Generally, there is no pain or discomfort connected with a brown recluse spider bite initially. If there is pain, it is often a mild burning sensation. After 2-8 hours, the pain becomes intense, oftentimes to an excruciating degree. At the site of the bite, there is an area of redness covering several centimeters across with a middle region of paleness in some cases.

After 24 hours, a blister filled with fluid forms and bordered by an area of inflammation. A rash the same as measles might also develop on the adjacent skin. This might co-occur with a systemic flu-like condition involving nausea and/or vomiting, fever, malaise and muscle pain. In most instances, the effects of a brown recluse spider bite cease and settles on its own in around a week.

Long-term complications from a brown recluse spider bite

In some cases of brown recluse spider bites, they become necrotic where the affected tissues die and starts to decompose. This puts the individual at higher risk for secondary complications especially a bacterial infection that enters the bloodstream. Remember that this is an extreme outcome and quite rare particularly in areas that have easy access to medical services.

The necrosis of the lesion is a process that arises over several days and typically instigated by a change in the color at the middle of the original lesion into a dusky blue or deep red. This area later turns numb as the nerve endings in the site die.

A scab forms that eventually breaks down into an ulcerated hole in the skin that continues to widen over the initial 10 days or so, usually no bigger than 1-2 cm in diameter. A lesion in this size generally heals on its own after several weeks, usually without any scarring. As for larger lesions, they take a longer time to heal and rare cases can be large enough to necessitate surgical excision of the necrotic tissue as well as skin grafting.

Quick Note / Disclaimer

The material posted on this page on brown recluse spider bite is for learning and educational purposes only. To learn to recognize the indications, register for a first aid and CPR course with Mississauga First Aid.

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