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Signs and Symptoms of a Poisonous Spider Bite

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Signs and Symptoms of a Poisonous Spider Bite

Jun 02, 2017

In the United States, there are two breeds of poisonous spiders to be worried about: the black widow and the brown recluse. We’ve all heard horror stories about these creepy creatures, but what really happens if you get bit by one? And what can doctors do about it? Emergency physician Dr. Troy Madsen shares the surprisingly non-lethal symptoms of a spider bite.

Episode Transcript

Interviewer: Poisonous spider bites, what should you do if you get bitten? That's next on The Scope.

Announcer: This is "From the Frontlines" with emergency room physician, Dr. Troy Madsen on The Scope.

Interviewer: Dr. Madsen, you know, for whatever reason, spiders will instill a bit of fear into a lot of people, right? Nobody wants to get bitten by a spider but realistically, it's just kind of the poisonous ones you have to look out for.

Dr. Madsen: That's right. It is. You know, we often have people come to the ER saying they've been bitten by a spider, they aren't sure if they have but they may have an infection or an abscess. In those cases, honestly, I don't know if they've ever been bitten by one, but you're exactly right. It's really just the poisonous spiders that we really worry about in terms of more serious symptoms and more concerning things.

Interviewer: All right. So a regular spider bite probably nothing to worry about unless you do start seeing an abscess or some infection then you would want to get that treated. But what are we talking about poisonous spiders? I understand there are two essentially in the United States. You've got the brown recluse and you got the black widow.

Dr. Madsen: That's right.

Interviewer: If I get bitten by either one of those, is that a big deal?

Dr. Madsen: Probably not a huge deal. Let's say that right off.

Interviewer: Because I was terrified of black widows as a kid.

Dr. Madsen: Oh, me too. And see, I'm just scared to death of those things, thinking if they bit you, you were going to die.

Interviewer: Yeah, yeah.

Dr. Madsen: That's not the case. I guess we could talk about black widows first because when I think about it as a kid, seeing a black widow spider, when your friends told you they had a black widow spider in the window, well, it was just like, "Wow, stay away. That is just so scary."

Interviewer: That's right.

Dr. Madsen: Impending death. That's not the case. If a black widow spider bites you, it's one of these things where it just makes you feel really miserable and kind of the classic thing is someone may come to the ER and maybe they know they've gotten bitten by a black widow spider, maybe not, but they just have tons of abdominal pain and you push on their abdomen and it's very rigid, almost like something where you would think they had like some sort of a severe infection in their abdomen, but that's classically what it causes. It causes nausea, vomiting. People just feel awful.

It's the sort of thing where I'll give some fluids, some nausea medication. They often require pain medication or something just to calm down their nerves because they're so tense from it. But then it goes away. It might take a couple days, but it's not going to kill you.

Interviewer: So if you're out in the wilderness on your own, you didn't have medical attention, you would feel pretty cruddy for a couple of days.

Dr. Madsen: You would.

Interviewer: That's the biggest. And then dehydration probably the biggest danger.

Dr. Madsen: Exactly.

Interviewer: If you're nauseous and throwing up. Would you throw up from a black widow spider?

Dr. Madsen: Absolutely.

Interviewer: Nauseous. Okay.

Dr. Madsen: Yeah, and it's one of those things it's like let's say you get food poisoning or you get some sort of viral illness. It's the same sort of thing where if you're otherwise healthy, probably not a big deal, you're going to feel awful, but you're going to get over it. But if you have other issues like maybe heart disease, diabetes, issues where you're already maybe having some health issues and then you throw in that dehydration along with it, that could cause some bigger problems, so that might be a reason where you need some medical attention for that.

Interviewer: All right. What about the brown recluse spider? Here in Utah, people say they get bitten by them. This is like the ongoing debate, right?

Dr. Madsen: Yup.

Interviewer: Like one person will say, "Yeah, they're absolutely in Utah." But a lot of other people will say, "No, they're not."

Dr. Madsen: That's right. And from everything I understand they're not in Utah. And I agree. I have people come to the ER who would swear they have been bitten by a brown recluse spider and who knows? I can't say they have or they haven't. Maybe it traveled here on a moving van from Alabama. Who knows? But these are primarily in the Southeastern U.S. We have a spider in Utah called the hobo spider that is brown and looks like a brown recluse spider, so that might cause some confusion. But the hobo spider doesn't cause the problems that the brown recluse causes. And it can maybe cause local infections, some issues there.

But the brown recluse, really the big thing with that is it causes a lot of skin breakdown where it bites. So unlike the black widow that causes a lot more symptoms like nausea, vomiting, a lot of symptoms all through the body, the big issue with these brown recluse bites, and I saw this when I worked back in Ohio, is it causes lots of skin breakdown, but quite honestly, there's not a ton we can do for that. Sometimes, with these areas, you know, you can see an area maybe a few inches wide where it just eats away at the skin, takes several weeks to really see this progress.

Some of these cases, people eventually require a skin graft to treat that area, but it's also one of these things where if you're rush to the ER, maybe we could try on an antibiotic. I mean it's questionable. Is there stuff that really prevents this? I haven't seen anything convincing. But you can try stuff. Maybe it helps, maybe it doesn't.

Interviewer: All right. And again, is it a painful thing so maybe some pain medication would be a good idea and stuff like that?

Dr. Madsen: Yeah, maybe some pain medication, you know. Again, we see lots of people who swear they've been bitten. Who knows if they really have?

Interviewer: All right. So I think we all have already covered the treatment. Brown recluse not necessarily a lot you can do in the short term.

Dr. Madsen: Not right off. I mean, if you're absolutely convinced and you know it's a brown recluse, maybe get checked out, maybe we can try something.

Interviewer: Got you. If you see your skin starting to disintegrate, then you know it wasn't a hobo spider.

Dr. Madsen: That's right.

Interviewer: And then for the black widow, abdominal pain the thing to watch out for there or the thing that you would treat is if there was actually throwing up to make sure that you stay hydrated.

Dr. Madsen: Exactly. Or if you're just in so much pain you can't tolerate it, you may need some pain medication.

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