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Anyone with a bad reaction to a brown recluse spider bite typically needs surgery to stop the ugly, spreading lesion. But that may not be the only option, now that a doctor pioneered a new treatment with a common skin medication – on himself.
Self-experimentation by doctors had its heyday in the 19th and early 20th century, and curious clinicians have never stopped. The German doctor Werner Forssmann, for example, performed the first human cardiac catheterization on himself in 1929 after dreaming it up in a bar and tricking a nurse into helping him, according to NPR.
Dr. Chris Schulze didn’t try anything so drastic after getting bit on both elbow pits cleaning up a rural property in Texas, however. He simply noticed the bottle of wart remover in his medicine cabinet just might have the right molecules to halt the spread of the lesions, at least in his own case.
Schulze did some research on brown recluse venom. He found a paper in which some of his medical colleagues in the research field detailed the minutiae of how brown recluse venom attacks mammal tissue and breaks it down.
“By the time the lesion can be identified as a brown recluse bite, it is already into the long-lasting ulcerative phase with ever-enlarging skin necrosis,” Schulze wrote in his article for Emergency Medicine News. “A paper from the University of Arizona identified a particular enzyme in the venom that cleaves the heads off long fatty acids and then connects the ends to form large cyclo-alkanes, which may be pro-inflammatory and may be the persistent cause of the enlarging necrosis.”
In other words, the brown recluse venom seems to work by messing up the chemistry of your cells. The venom enzyme breaks apart the fatty acids your cells need to live and heal.
Schulze was treating those elbow pit bites in the recommended way, hoping they would clear up before turning into necrotic lesions, but he had no such luck, he said.
The lesions were spreading, and the intense itching woke him up one night, which is when he noticed trichloroacetic acid (TCA) on his medicine cabinet shelf. This is a common wart and skin tag remover, also used in chemical skin peels.
But by virtue of his medical expertise, Schulze knew trichloroacetic acid also denatures proteins and is used for this in laboratory settings. He painted some on the lesions, and it cleared up his spider bites over a couple weeks with no scarring. This treatment worked not only on the first bites, but ones he sustained later on several occasions – early application even prevented lesions from forming in the first place, he said.
“I propose that TCA is able to denature the offending protein-based toxin directly, rendering it ineffective by virtue of its ability to penetrate the top layers of the skin and its protein coagulation properties,” Schulze writes.
New treatments in general must go through a lengthy approval process, but Schulze said clinical trials on spider anti-venin or other spider bite treatments would be nearly impossible because of the rarity of such bites. The advantage of TCA is that it’s common, safe and emergency clinicians can try it out before other, more drastic treatments.
And Schulze proposes TCA could treat other bites and stings in which the venom is protein-based.
“Here in the southern United States, we also have a nasty moth caterpillar, locally called the asp or pussy caterpillar, which inflicts a painful sting via tiny spines on its hairy projections,” Dr. Schulze said. “The pain from these is notoriously difficult to treat, but the venomous component is known to be a protein-based enzyme and the envenomation is superficial, a perfect candidate for TCA. Likewise, jellyfish stings are by tiny nematocysts that inject protein and peptide toxins into the skin, providing another possible substrate for TCA.”
What Happens When You Get a Brown Recluse Bite?
Brown recluse spider bites are quite rare – as the name suggests, the arachnids are known for being reclusive.
But when one does bite you, it can be life-threatening. You also may develop a necrotic lesion around the bite in which the tissue dies. Currently, the only treatment for such a reaction is a scarring surgery to remove a large swath of flesh centered on the bite.
The bite of a brown recluse spider leads to a mild stinging, followed by local redness and severe pain that usually develops within eight hours but may occur later, writes MedicineNet author Melissa Conrad Stöppler, MD.
Some reports of brown recluse bites describe a blue or purple area around the bite, surrounded by a whitish ring and large red outer ring in a "bull's eye" pattern. A fluid-filled blister forms at the site and then sloughs off to reveal a deep ulcer that may turn black.
What Should You Do if You Get Bitten by a Brown Recluse?
Dr. Stöppler recommends the following if you think you have been bitten by a brown recluse:
- Wash the bite area with soap and water.
- Elevate the area to prevent spread of the venom.
- Tie a snug bandage above the area (if on an arm or leg) to further reduce spread of the venom, but do not make the bandage too tight that it impairs the blood circulation.
- Always seek immediate emergency medical care. Doctors' use different types of medications to treat spider bites, including pain relievers, muscle relaxants, and/or corticosteroids. Sometimes hospitalization is required after black widow or brown recluse spider bites.
- If possible, retrieve the spider and bring it with you to the health care practitioner so that it can be definitively identified.
- A tetanus booster shot may be necessary, depending upon the date of the patient's last immunization.
- Calling the Poison Control Center (24-hour hotline at 1-800-222-1222 in the U.S.) allows you to reach toxicology experts who can work with a health care provider in establishing the proper diagnosis and management of a spider bite.