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ER or Not: Sudden Severe Headache

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ER or Not: Sudden Severe Headache

Sep 23, 2020

You are suddenly hit with a severe headache that you’ve never experienced before. Maybe you pass out; maybe it makes you sick to your stomach. Should you go to the ER? Emergency physician Dr. Troy Madsen says these “thunderclap headaches” might be a sign of something much more serious. On this episode of "ER or Not" we talk what potentially life threatening problems that a severe headache might be a sign of, and how to distinguish them from a normal headache.

Episode Transcript

Interviewer: You get a crazy severe headache out of nowhere. ER or not? That's next on The Scope.

All right. It's time for ER or Not, where you play along and decide whether or not something that happened is worth going to the emergency room or not. We're with Dr. Troy Madsen. He's an emergency room physician at University of Utah Hospital. Today's ER or Not, you get a crazy severe headache out of nowhere. Just, bam, it hits you. Should I wait a few minutes, or should I think about going to the ER? ER or Not?

Severe Headache and Vomiting

Dr. Madsen: I'm going to ask you a little more about this. Have you had a headache like this before?

Interviewer: No. This was just something, never experienced anything like this.

Dr. Madsen: Nothing?

Interviewer: No.

Dr. Madsen: Severe headache?

Interviewer: Yeah.

Dr. Madsen: All of a sudden?

Interviewer: Maybe mild headaches before, but nothing like this. It just all of a sudden, bam.

Dr. Madsen: Did it make you pass out or cause you to feel sick to your stomach?

Interviewer: It did not make me pass out. Caused somebody to feel sick to their stomach, sure.

Dr. Madsen: Okay. Yeah. These are typical questions I'm going to ask someone. Again, I'm imagining you're a family member calling me on the phone telling me, "I've had this severe headache. It just came out of nowhere. I've never had headaches before. Otherwise, feel okay." I'm going to say, "Go to the ER."

Interviewer: Okay. So severe headache out of nowhere, no other symptoms, still go to the ER?

Dr. Madsen: Yes.

Interviewer: Put a little nausea on top of that or passing out, then definitely.

Dr. Madsen: Absolutely.

Interviewer: I'd imagine go to the ER.

Causes of Severe Headaches

Dr. Madsen: Yes, absolutely. These are cases where the big thing I'm worried about is what's called a subarachnoid hemorrhage, which is bleeding in the brain. So you can have an aneurysm. Maybe 1% to 2% of the population, of all of us, just have possibly little brain aneurysms, just something we have and we may not know it. But these individuals that have severe, sudden headaches like this, the big thing I'm worried about is something rupturing with that aneurysm, bleeding out, and that's what's causing the severe headache.

Classically, what will happen is someone will say, "Out of nowhere I had the absolute worst headache of my life." They describe it as a thunderclap headache, just like that thunder just hitting you all of a sudden. Sometimes they may pass out. Sometimes they may feel very nauseated. They may have other symptoms as well with it, if the bleeding is severe, like difficulty speaking or weakness. But really, if you have that severe, sudden onset headache, you need to go to the ER to get that checked out.

Interviewer: So these aneurysms, otherwise completely healthy people could have them?

Dr. Madsen: They might, and that's the thing. It's not something where I'm going to recommend that people just go and say to their doctor, "Hey, I heard this guy say that maybe 1 or 2 out of every 100 people have these aneurysms. I want to get checked for this." Because most people go through their whole lives and it's never an issue. But in some cases, for whatever reason, there may be something about it, either it's large or it's been weakened for some reason, these aneurysms can rupture, and then can cause these severe symptoms.

Interviewer: Are there instances where you could have this sudden severe headache and it is something else? What I want to say first of all, if you do have this go to the ER.

Dr. Madsen: Yes.

Interviewer: But in the interest of not freaking everybody out, could there be other reasons?

Dr. Madsen: Oh, absolutely.

Interviewer: Okay.

Thunderclap Headaches

Dr. Madsen: Just because you have this doesn't mean you've had a ruptured aneurysm. When studies have looked at it, they've found that about 10% of people who describe these thunderclap headaches, these very severe, sudden headaches, do end up having some sort of bleeding in the brain. That means the other 90% just had it. For whatever reason, it just came on. The big thing I'm thinking about in the ER is ruling out the bad stuff. Oftentimes, that means getting a CT scan of the head to look for any sign of bleeding there, making sure there's no sign of that, and we may have to do some additional tests as well.

But at the end of the day, 90% of the time or more, I'm telling people, "Hey, you had a severe headache. I don't have a great explanation as to why. I may look for other causes as well, but at least we know it's nothing very serious like this."

Interviewer: Then, that buys you some time to maybe look into the other reasons.

Dr. Madsen: Yes, exactly.

Interviewer: But definitely, those thunderclap headaches, go to the emergency room.

Dr. Madsen: Absolutely. Yep. I've seen cases of people who have come in, young, healthy people who have come in and said, "I've had this severe, sudden onset headache." We start the testing. Within 30 minutes they are not responding, because the bleeding has gotten so severe. We're getting the neurosurgeons down there emergently. So one of those things that I don't want to scare you with this, but severe, sudden onset headaches you want to take seriously.


updated: September 23, 2020
originally published: May 13, 2016