Why does needle phobia cause fainting?

[chickenninja]

Why though? Other phobias don't. I've known people petrified of spiders but never on the verge of passing out.

I'm asking from a personal point of view, I've always fainted before an injection from an early age, my brother did too.
I've got used to jabs now as I have to have blood tests regularly but I also have to have a cannula which makes me feel like I'm going to faint or be sick. Why does this happen and how can I control it?

Is it really a 'phobia'? Because I don't like slugs or heights but I wouldn't have such a physical reaction to this. I know it's funny to some people and some people just say toughen up, but how..?

It differs from other phobias in that there is a specific physiological reaction. Feeling faint is linked to reduced blood pressure which may be an evolutionary reaction to the possibility of blood loss: en.wikipedia.org/wiki/Blood-injection-injury_type_phobia

Pain can cause a vasovagal response which can cause nausea and fainting. The pain from a needle is obviously minor but if you're terrified and anticipating it, any physical response may be worse.

Also I suspect a large proportion of those who say they have a phobia of spiders, in fact have a strong dislike, aversion, or even fear, but not a psychological phobia. The same as you don't like slugs or heights but you don't have a phobia of them.

I also think the spider thing is exaggerated because people (especially women) are brought up with this idea that spiders are some horrid, nasty creatures, and it's acceptable to have an over the top negative reaction to them, which wouldn't be generally been seen as quite so acceptable in response to, say ants, or dogs. It's a media trope, isn't it? The woman who screams when she sees a spider. So young girls just assume, that's what you do when you see a spider. And so they grow up afraid of them.

Thank you for the link, that is interesting. I don't know there was a name for it.

sm.stanford.edu/archive/stanmed/2013spring/article6.html

I think it can happen with other phobias. I have a severe phobia of vomit as well as just generally being a bit squeamish.
If I see someone vomiting/feel sick myself I either pass out or have a panic attack. I’ve passed out visiting someone in hospital before just through the fear that I might see someone being sick.
I’ve also fainted during a smear test before when the nurse insisted on talking me through it in graphic detail despite me reassuring her I had no interest in gory details

I don't mind needles going in but needles taking blood out and I start to faint. If I can get on a cold floor or chuck cold water over my face and wrists I can hold it off. It's been horribly embarrassing at times. I also can't stand still for long as my blood pressure drops and I feel faint.

Also happens if I or DC cut ourselves :(

Starting to feel queasy even just typing this.....

Your blood pressure drops too fast if you faint afterwards. It goes way up in fear and then plummets when it’s over.

I can go very woozy about teeth. The first time it happened someone was talking about how they damaged theirs and I suddenly felt the room swim and had to sit.
Not a fan of children wobbling theirs!
Generally OK with my own though.

I did also go woozy when DS1 fell off a seat and got an egg on his head. By the time a first aidee came to the table, he was fine and I was with my head between my knees. I think being hungry, BFing and going down with an illness (I realised after) were factors. Most of my faintness incidenrs have involved hunger especially in pregnancy/ BFing.

I don't have a needle phobia but started feeling faint (and have fainted once) at the sight of blood after having a bad experience during a blood test (lots of blood involved). Like pp says I think blood pressure is involved and there's only so much you can do about it. I'm not particularly fussed about blood, it's just that my body freaks out upon seeing it!

I've been told (medical informant) that my brain goes into overdrive to protect me from a perceived threat, and I have a panic attack. The panic attack causes me to hyperventilate. Hyperventilating makes me faint. It's a multi stage process, and can take quite a while, but once I get on that train, and a little way down the line, I can't get off. Fun times.

It can happen with no phobia.

Many years ago I found myself helping science (and my bank balance) by taking a pharmaceutical trial with a couple of friends. Part of the deal was we all had a pre-trial blood test. There were 20 of us in total, and we all lined up sleeves off to give a needleful. I was chatting to my friend one side, when all of a sudden we realised there was a space behind me. My other friend had fainted clean away.

What was most memorable was the total lack of concern from the head doctor, who just said "You'd have thought with this many medical students, someone would know what to do ..." which caused a flurry of activity. Turns out it's a good idea to pump the legs to get blood back to the brain asap. Which did the trick.

When my friend came round, it was all very odd. He'd never fainted before in his life, and certainly had no fear of needles or blood. With annoying vagueness the head doctor just said "These things happen sometimes. No idea why."

We all went on to have EEGs and ECGs and blood works for the trial which passed us all A1 fit and healthy.

(If you are taking an oral HRT supplemant that used to be available only as an injection, then you have us to thank )

With annoying vagueness the head doctor just said "These things happen sometimes. No idea why."

I think this is what bugs me, the lack of knowledge or reason behind it. I imagine it could be a serious problem if someone was refusing cancer treatment for example because of their medical phobias.

But saying that, I've learnt a lot from this thread so thanks very much for the links and information, I shall read up on it later.

It can happen with all phobias actually. Fainting isn't specific to needle phobia - odd assumption it was tbh.

I have absolutely no idea why it happens but I used to do this as a kid and it was very much a case of uncontrolled anxiety triggering a physical reaction. I can only liken it to a panic attack. My anxiety would spike and then my blood pressure would drop and I'd get very woozy and faint. It became a self fulfilling prophecy after a while, the fear of fainting created more fear which made fainting more likely. It was very weird.

Hasn't happened in years, mind...

It happens to me. I don't even have a phobia of needles. But half of the time I have blood drawn I will get whoozy or faint.

I faint when in pain too back spasm, wisdom tooth removal. I'm a nightmare.

I fainted once on a railway platform reading a magazine article about how nose jobs were performed (it was in great, disgusting detail). Everything just went dark and down I went. I’m not even squeamish. So I bet it does happen with other phobias.

Could it be because the needle phobia is the only one I can think of (at the moment!) that always has to be fully confronted and endured? I hate spiders but have never fainted on seeing one. But that's because I run away or kill it. I think if it had to be put on my face or something I would faint! Heights, snakes etc are the same - you are unlikely to encounter a full exposure scenario (skydiving or being bitten by a snake respectively). With a fear of needles every single time you encounter the phobia the absolute worst possible scenario happens - the needle goes in your arm. Could it be the total 100% exposure needle phobics have that causes fainting, rather than the nature of the phobia itself?