Why does your arm hurt when you touch it two hours after you get a vaccine?

Answer 1

The local tenderness and sometimes redness, swelling, and hardness in the area where a flu vaccine has been given is the most common side effect of the injection. It is the local muscle tissue noticing and reacting to the "foreign invaders" in the vaccine (the virus particles in the vaccine). Although the invaders can't make you sick, they trick your body into thinking they can, so your body goes to work trying to increase circulation to the area and sending the immune system cells that fight viruses to the area. That response can make your arm sore. It can last for 2 to 3 days, and sometimes it is even worse the second day. Don't try to avoid moving the arm, using it will help it get better faster, so work through the discomfort and use it normally as much as you can. You may find it helps to put a moist warm compress (washcloth or something similar) on the area that hurts for 20 minutes and see if it makes it feel better.

Answer 2

Because there are three shots in one !!!!!!!!

Yes, usually the tetanus booster given today is the TdAP, which has tetanus, diphtheria, and pertussis (whooping cough) all in one needle. But that's not why the tetanus shot hurts so much and for so long after it goes in.

First, the tetanus booster serum has foreign proteins and is adsorbed in a alumina solution. Those reagents irritate the muscle when the tetanus shot goes in your arm. Tetanus toxoid itself is a de-activated form of tetanus, and that causes your body to react just as if it were really tetanus. Tetanus makes the muscles sore and stiff, so a tetanus shot makes your muscle sore and stiff just as if you had the real thing.

Mainly tetanus shots hurt because they go kinda deep into your deltoid muscle up high by the shoulder. And the doctor or nurse giving you the tetanus shot pushes down really fast on the syringe piston and shoots the tetanus booster into your muscle really fast. That's why it's called a tetanus shot, because it shoots into your muscle. When the tetanus booster shoots in it bruises your muscle too, and that's part of the achy feeling when the tetanus goes into your muscle.

Tetanus shots hurt more if you don't relax your muscle before the doctor or nurse sticks the needle into your muscle. I mean duh! Of course a tetanus shot hurts more when it shoots into a tight muscle. Also, it's natural for most of us to contract the deltoid muscle when we feel the tetanus shot pushing into the muscle. That makes the tetanus booster hurt alot more than if we could resist the impulse to contract the muscle as the tetanus pushes in.

Actually a few weeks ago I got another tetanus booster and it didn't even hurt a bit--a big first for me! I wore a really comfortable grey tank top with roomy armholes, and I really relaxed my left deltoid muscle (I'm a righty) by letting my sleeveless left arm hang comfortably down by my side and resting my left forearm on my lap. I actually saw the nurse attach the one inch needle to the syringe and I saw the tetanus booster in the syringe. When I saw the one inch needle I knew it was long enough to stick kinda deep into my muscle, so I told myself to really relax my muscle and keep it relaxed the whole way through getting the tetanus booster. The nurse grabbed my deltoid muscle really firmly up high by my shoulder and I couldn't see the needle stick into my muscle. I saw the nurse's hand go down so I knew the needle was in my muscle but I didn't feel it! I concentrated on keeping my muscle nice and relaxed. Then I saw the nurse's thumb push down on the syringe piston, and I knew the nurse was giving me the tetanus on my muscle but I didn't feel it go in! Then the nurse pulled the needle out of my muscle and it was over and done! So all of you tetanus needle scaredy-cats, that's my best advice--wear a tank top so your arm is sleeveless, and keep your muscle relaxed when the doctor or nurse pushes the tetanus onto your muscle, and you shouldn't feel a thing. Not a prick, not a muscle cramp! Also it helps to get your tetanus booster every 3-5 years--not the 10 years they say it's good for--because the longer you let your tetanus booster go, the more it reacts when you finally get your tetanus. Getting a tetanus booster every 3-5 years means your body is not quite as sensitized to the TdAP serum (you still have some immunity left) so it doesn't react so much and sometimes--like me last time!--you won't even feel the needle or the tetanus shot go in your muscle! Good luck! And go get your tetanus shot soon!