I was just having a routine blood draw today; and, granted, it was just taking blood out, not injecting something, but it made me think:
Why is it that when you get an injection of something–say, flu shot–it can really hurt, but this blood draw hardly hurt at all? The guy doing it was very skilled in his technique, but I wonder what the difference is since it’s all needles.
As an insulin dependent diabetic for the past 18 years, its just a matter of hitting or not hitting nerves. Sometimes when I inject it really hurts, almost like a bee sting. Other times there’s no sensation at all. Usually its somewhere in between.
Also, when you give blood the needle stays in longer but doesn’t penetrate as deep as with an immunization injection. And sometimes the pain can come from a chemical reaction with what’s being injected (i.e. tetanus shots can hurt like hell a second or two after the needle!)
The method of injection makes a big difference too. With a subcutaneous injection, the needle is inserted into a fold of skin and will not cause much pain unless it hits a nerve ending that is sensitive to pain. Insulin injections are subcutaneous. When you give blood, the needle is inserted through the skin into a vein just below the surface of the skin (intravenous). Veins themselves are not sensitive to pain, and so the needle should not cause pain unless it is inserted close to a nerve ending. Flu shots (and many other vaccines) are intramuscular – the needle is inserted through the skin into a muscle, usually at least an inch deep. This has a much better chance of hitting a nerve ending (or several), and the fluid that is injected can cause irritation due to its acidity, water content or the effect the injected agent has on muscle cells or the immune system. The immune response caused by a vaccine can lead to noticable irritation at the site that lasts quite a while.
I should add that needles used for subcutaneous injections can be very fine, and so cause a minimum of pain. Needles for intramuscular injections have to be larger so they can penetrate muscle tissue, so they affect an area that is not only deeper but wider. Intravenous needles are the largest (for drawing blood, anyway; needles for infusing IV solutions aren’t necessarily big), but the chance of hitting a nerve ending is lower.
I don’t know but Vistaril (anti-nausea) hurts like a bitch when injected. Had it in my teens and the burning actually made me cry.
Potassium in an IV is awful, too.
Thanks, all. Dang, Abbie, that sounds horrible. Hope you never have to have either again.
As long as we’re on the subject…Why do some shots go in the arm and others in the tush?
Visteril, that is.
Vistaril is given for allergies.
The most painful injection? Sterile Water, IM. Ouch ouch ouch ouch.
Not that there’s any reason to ever get such a shot, but because of the difference in osmolarity, it will lyse many cells in the area.
Amazing how much simple water can hurt.
In school, all the “expired” drugs were sterile water. Or any drug the “patient” was allergic to. The “good drugs” were always normal saline. So if you injected your buddy with pure water, he’d be pretty pissed. Then after he finished punching you in the face, and then purposely injecting you with the same stuff, you would learn your lesson!
… what a violent way to learn medicine.
There is no drug named Visteril, only Vistaril.
For that matter, why are vaccines given in different places just on your arm? It’s been years since I had that pre-college physical, but I recall the tetanus shot going into the muscle and the MMR (owwww!) into the softer tissue under the arm. I also got vaccinated for chicken pox at the same time and I think those were the softer tissue ones too. Why the difference? I thought they all pretty much worked in the same way?
and then there’s the whole BCG injection… now I have another scar dammit. Beats actually having TB though.
Every two weeks I have to get an intramuscular injection of a fairly viscous liquid. Since it’s so viscous, the needle has to have a large bore and you really have to push on that damn syringe plunger to force the medication through the needle. It seems like it takes about 5 minutes, but I guess it’s closer to 20 seconds or so.
Ouch. I’m cringing thinking about it.
Maybe I spelled it wrong and it’s Vistiril.
VistAril is given for allergies.
Vistiril/Visteril, however it’s spelled, is given for nausea.
Also, I’ve been told that some injections hurt more than others because the person doing it sometimes rushes it. The fact is that the material being injected needs to be taken up and absorbed away from the injection site, and if too much is injected at once, it hurts more as the pressure within the tissues is raised extensively. I asked a similar question some years ago. Probably in the archives someplace, but I don’t know how to search for something that old. xo C.
There is no other spelling of the name.
Vistaril is used for both allergy symptoms and nausea.
I have two questions about this post.
“Expired” drugs were sterile water? Does that mean an old drug loses its salinity, or that old medicines were delivered in sterile water? I don’t understand why either of those things would happen.
Medical students inject each other with drugs? Are you saying heroin or something? Didn’t sound like it…
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I’m suspending both of your medical licenses until you get this straightened out.
This question has not yet been fully answered.
Your body obviously has nerves in the skin to detect pain, light touch, position, temperature, etc. But it is more important to be able to feel light touch with your fingers than your back, for example, and this is reflected in how much area the brain uses to process these body parts. An injection in the back hurts less than an injection in the finger. Big needles hurt more than little ones (which also mske injections slower).
Some injections can be quite acidic. Xylocaine with epinenphrine, used to freeze lacerations before stitching, can burn. Injecting more slowly or with bicarbonate helps reduce this. Injections of potassium, rocephin, etc. are not pleasant.
Volume of injection can make a difference too. Injecting a lot of stuff into a closed place puts more pressure on the area than injecting a little bit of stuff.
This talk of expired sterile water and Vistaeril obviously plays an important and compelling role as well.
He meant that med students learned how to give injections by using saline in a syringe. If they were told to inject a drug named, say, Aba, they had to pick out a bottle labeled “Aba” with a non-expired date on it. Bottles with expired dates or different names, like “Abe”, had pure water in them. That way you get taught about how to pay attention without having fatal consequences result, like might happen in real life when they’re using the real thing.
Please allow me to clarify.
In class, during a Practical Examination (As in “We’re being tested” and not "We’re giving an exam), there would be a tray of various “drugs” These viles would have different labels as if they were really the drug it represented. It would have the name of the drug, the concentration, the expiration date, etc.
We would be randomly assigned several shots to give our “patient”. The patient was simply the student who went before we did. After you give your shots, you sit down and receive for the next test-taker.
So we look at the drug, and the amount to be give. Then go through all the “Patient Rights” and make sure to ask about allergies. Then we calculate how many CCs of drug to draw from the vile based on the dosage required and the concentration in the vile.
Then we make inject it using proper technique for that particular kind of injection (IM, SQ, etc.)
All the drugs are filled with Normal Saline. Normal Saline is set at the proper osmolarity so you can inject it easily and all day long with no ill effects.
But if the idiot about to give you a shot, forgot to check the damn EXPIRATION on the label. He may have drawn an “expired” drug. The “expired drug” was simply sterile water. This immediately let the shot taker know someone messed up.
The thing with sterile water, is it has a different osmolarity than the inside of your cells. Read up in osmosis to see how this causes your cells to explode and die. This causes a little discomfort. Unfortunately the person who suffers is simply the guy sitting there and not the guy who messed up. But isnt that how real life medical mistakes are??? The patient suffers for the doctor’s mistake…
The student would get a NO-GO on that station and would have to retest the next day. But not BEFORE the shot-taker gets to shoot the guy in the ass with a huge bolous of sterile water…
Barbaric and childish I know… but what do you expect from a bunch of Military guys?
Not to continue this hijack too terribly, but this isn’t uncommon at all. Dramamine, the most common motion-sickness (i.e. nausea) drug is an antihistamine; Phenergan the anti-nausea drug my doc prescribes for kidney stone attacks, is also an anti-histamine. I’ve had Vistaril as an anti-nausea drug, but it gives me a killer headache.
As for the OP, a lot has to do with what the shot is. At one point, I was in the hospital, had a serious kidney infection; my IV had jumped the vein, and no one on duty could get one re-started, so I had to have two antibiotics injected intramuscularly (in the butt). One of the antibiotics wasn’t too bad, but the other one burned like a sumbitch. Some nurses giving shots that burn subscribe to the “do it quick and get it over with” school of thought; others subscribe to the “if you slow down, it doesn’t burn as much” school. I have found, though, that if I voice a preference, only the really bitchy nurses will refuse to honor my wishes.