Fainting (Syncope): Get the Facts on Causes

Syncope - is the medical term for fainting or passing out. It is caused by a temporary drop in the amount of blood that flows to the brain.

Vasovagal syncope (vay-zoh-VAY-gul SING-kuh-pee) is one of the most common causes of fainting. Vasovagal syncope occurs when your body overreacts to certain triggers, such as the sight of blood or extreme emotional distress.

The vasovagal syncope trigger causes a sudden drop in your heart rate and blood pressure. That leads to reduced blood flow to your brain, which results in a brief loss of consciousness.

Vasovagal syncope is usually harmless and requires no treatment. But it's possible you may injure yourself during a vasovagal syncope episode. Also, your doctor may recommend tests to rule out more-serious causes of fainting, such as heart disorders.

Symptoms

Before you faint due to vasovagal syncope, you may experience some of the following:

Skin paleness
Lightheadedness
Tunnel vision — your field of vision is constricted so that you see only what's in front of you
Nausea
Feeling of warmth
A cold, clammy sweat
Yawning
Blurred vision

During a vasovagal syncope episode, bystanders may notice:

Jerky, abnormal movements
A slow, weak pulse
Dilated pupils

Recovery after a vasovagal episode begins soon after fainting, generally in less than a minute. However, if you stand up too soon after fainting — within 15 to 30 minutes or so — you're at risk of fainting again.

When to see a doctor

Because fainting can be a sign of a more serious condition, such as a heart or brain disorder, you may want to consult your doctor after a fainting spell, especially if you never had one before.

Causes

Vasovagal syncope occurs when the part of your nervous system that regulates heart rate and blood pressure malfunctions in response to a trigger, such as the sight of blood. Your heart rate slows, and the blood vessels in your legs widen. This allows blood to pool in your legs, which lowers your blood pressure. This drop in blood pressure and slowed heart rate quickly diminish blood flow to your brain, and you faint.

Common triggers for vasovagal syncope include:

Standing for long periods of time
Heat exposure
The sight of blood
Having blood drawn
Fear of bodily injury
Straining, such as to have a bowel movement

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[stephaniegarcia]

I’ve fainted so many times in my life, and its so nice to read everyone’s comments about their fainting experiences. I’ve found my people 😌❤️

[miledytrujillo]

It is so scary to be on the verge of passing out. I hate it

[tifflovessans]

I passed out because In dance practice some genius closed the windows on a hot day and my teacher panicked so much lol

[carolinecowan]

I passed out in highschool once years ago. Our class was watching a film and I started to feel light headed and nauseous, so I got up to go to the bathroom. On the way out, I banged my head on the class door frame, stumbled into the hall, and managed to get half way to the bathroom before passing out and falling into another classroom 😅 I can laugh about it now, but yeah...was pretty surprised to wake up to find half a dozen teachers around me and an entire science lab looking totally confused. Good times.

[thajasnethomas]

I was cooking noodles today, when out of nowhere, I started feeling hot. Never have I ever, in the history of cooking noodles, felt this way.
As soon as I served it on my plate, I rushed to the dining table, kept my plate and went to get some fresh air. Still feeling suffocated, I ran to the table, sat down, and then rushed to the bathroom, sat there and felt better.
Anyone who has been through this knows that the traumatising effect doesn’t come during the episode but is what comes after it.
My mom described how pale I had become when this happened, and how my lips turned paper white.
It was so scary, but luckily, I did not faint!

[sarahfreeman]

So I passed out today. This was a scary experience. It was after I ran during PE outside. After we were done running we went in a circle and the pe teacher explain what we were doing. She put us In groups and in our groups I was standing there and I felt like I was going to throw up. And then I started to see little white things in my eyes and everything was turning black. I started to woble. So I told a person name Olivia in my group and told here that I did feel good. I told her because she was the only girl in my group. And then the pe teacher walked by and then everything went black. The girl I told was next to me and so was the pe teacher and they caught me. I only passed out for 30 sec they said. And when I was awake I was sitting on the ground. Olivia the girl in my group said that I scared her.

[Lonystal]

I've only passed out once, and it was when I was running to catch the bus in the morning, having not eaten breakfast at all. I ran way too fast and no warmup at all. When I got in the bus it was crowded, and there was no free space to sit. So I had to stand. I said hi to my friends and just stood there trying to catch my breath. I was also staying close to the door so that if I throw up (because I was feeling nauseous) I'd atleast not gross out the entire bus. I remember I tried to catch my breath for like 2-3 minutes when I don't remember nothing after that. Apparently I had passed out and almost swallowed my tongue, but thanks to a friend of mine he risked his fingers to pull my tongue back up.

All I know is that it felt like I was in a deep sleep, just random dreaming.

When I woke up I was wet (people trying to wake me up by washing my neck and face with water), and everyone was around me like damn.

A friend described to me that I had passed out so dramatically, like just slowly fell on my knees and then fell down completely.

I believe this was due to hypoxia. I was 17 btw.

[Cympdragon]

Anyone else feeling any of these symptoms posted below while visiting places like doctor/dentist or hospitals?
Lightheaded (A blackout feeling as you're about to faint), a very warm sensation feeling in the head, suddenly feeling of nausea.
I usually get these symptoms and starts to feel unwell after arriving the room in these kinds of places.
Other symptoms i have experienced are blurry vision, feeling of dizziness like the room is spinning, and suddenly hearing loss as i couldn't hear what the person was saying to me.
To feel better i usually have to bend my head downwards while sitting forward and have some water. It usually goes away eventually so i can proceed but from experience it seems to occur around 5 minutes after entering the room. This is a horrible feeling and i do suffer from anxiety and asthma.
Thankfully i have never fainted in my life but i must have been really close.

[pain]

When I fainted today, it was because of low bloodmpressure. I started sweating alot, Everything went dark but I could somehow see, everything became disoriented, my legs weakened and I collapsed. THAT WASN'T FUN AT ALL!

[sarahsingt]

I almost fainted in Grade 4 and 5 when our teacher at school talked about our organs. I couldn't stand to hear this. I was feeling bad and couldn't see anything hearing this. I was very sensitiv in that theme. But I was allowed to leave the class room in time before I would have fainted. Since I was 11 1/2 years old I can stand hearing such things. And in the age of 13 I almost fainted because I was so sad that I wanted to die. But I stopped the process in time talking hope into myself and pushing the feelings away from me.

[orlithik]

Having read some comments, thought I'd share my experience.
The very first time I passed out, I was on a shopping trip with my best friend. We were sitting on stools in a cafe on the sidewalk, waiting for our drinks, when all of a sudden I felt my vision go blurry. At first there was an abundance of light like an overexposed photograph; then a point of hyper focus, where the only thing I could see was the ketchup bottle; this was accompanied by a sudden loss of equilibrium and nausea. Next thing I know, my vision is darkening. The last thing I remembered was telling my friend 'I'm passing out'.
When I came to, I was on the floor on my side with a bunch of waiters around me and my friend squeezing a water bottle over my head. When I finally got her to calm down, she said I tipped back from my stool and lay flat on my back. Apparently I lay still and unresponsive for about 7 seconds and my eyes were open the whole time; I don't remember any of this and wouldn't have believed it had one of the customers not filmed the whole thing.

To this day I have no idea what happened. But I've learnt to watch out for the signs.

[cunninglus]

2 years ago, I passed out in the bathroom. My stomach was hurting so bad because of what I ate. I was shitting small amounts and it's frustrating I kept coming back in the bathroom. It got to a point that I became light headed. I couldn't take the pain in my stomach anymore, it was like closing in, I could barely breathe. The pain rose up in my head so I stood up to get out so I can lie down on the bed. But by the time I got to the sliding door, my vision started to blur and all I could see were lines that are sparking and I blacked out. It happened for what felt like minutes until I woke up and I was already lying on the bathroom floor, I couldn't stand and my head hurts. I got a pretty huge bump on the back of my head, I was glad that I didn't get a concussion though. I also got cold sweat, like my whole body was on ice. Lesson learned. When you are about to faint just lie down immediately, I could have broken my skull that time by the lavatory, It was deadly close from where I was standing.

[mitskisontop]

I fainted a few minutes ago.
I was hugging my mom before she went to work and all of a sudden I felt dizzy and everything when pitch black and when I wake up my mom is crying I felt weak and I kept hearing her voice but I was unconscious and couldn’t respond back and when I finally get up I get a headache. And that was like 6-8 minutes ago,

[kayleighbaetens]

I used to pass out every time I saw blood or when I knew blood would come, like if I took a bandaid of... I don't have it anymore, but I passed out in preschool ones, I was chill afterwarts but everyone was freaking out.

[unknownf]

Does anyone else move and shake a lot while having a syncope?or doni have epilepsy and i dont know about it.
Btw i get only one episode per year and that too whenever i am near the end of my period.

[notaotaku]

She looking at the camera makes this even better.

[jredfern]

I passed out last night my dad Hugged me and everything went blurry and I was on the floor shaking then I was back up my mum thought I was joking then I said to my mum something just happened and I panicked and I had to go outside

[TheEveHart]

Since everybody else is sharing their experience, so will I:

So today I was at church and I was helping with stuff when I randomly started feeling nauseous so I went to the bathroom and sat down. I felt like I was going to throw up for a little bit but then my vision started going really blurry so I walked into one of the stalls and sat on the floor, I blowed my nose and I couldn't even hear that because my hearing was going away. I don't remember much from there, but once I woke up, I felt all better, but I was covered in sweat, and I could finally hear and see. It felt like I was looking through a kaleidoscope before I fainted.

[tillyrosee.e]

needles: *exists*
Me: *nervous sweating*

[sunshine-ff]

Today was the worst day of my life, i was in social studies class and we were talking about blood in the French and Indian war and scalping. And I literally cannot handle anything related to blood and I passed out and hit my head on the tile floor and my friends were trying to shake me and my teachers were trying to yell my name so I would wake up and after I woke up I had a headache all day. So thank you for this video now I kind of have a better understanding of what happened to me today 🥺