First B12 shot today

Just got my results from the doctor today and they told me I needed to take a b12 shot and b12 supplements. I just had my first b12 shot earlier this afternoon, and I felt absolutely nothing at all. I was told it usually starts working within minutes to hours, and someone else said it could take up to 3 days.

Does anyone here know how long it should take for me to notice it? I actually felt a little more tired than normal after I had it, and my arm started aching.

[Londres70]

I would give it about a week to see a difference, but I cannot see how one shot is going to be making you feel great in "minutes to hours."  

Keep the aching arm mobile; this will help decrease the pain and help disperse the medication.  If the injections are IM (intramuscular) your arm probably will be sore.  They should rotate the arms with each shot to prevent overuse of one arm.  

[sunday23]

B12 a vitamin that will help for the absorption... what is the reason why giving you a shot? mostly vegetarians must have it because that is the vitamin that they are lacking...coz its main source is animal food.. you can also can have it by eating fish, milk, cheese etc.
what you are experiencing right now is one of the adverse effect of it, sometimes you will experience fever..but if it persisting for a longer time or days and you felt that you cant endure it then come to your doctor as soon as possible

[suzzyq2]

Sometime certain  people can not absorb B12. It iscalled Pernicious Anemia and will need B12 shots for the rest of there life  I have it  and  my doctor told me the is a new B12  lozenges  I bought it the other day.  I found it at Rite aid in the vitamin isle you can't  just  swallow it   you have to put it under your tongue and let it absorb that way so swallowing a B12 vitamin will not work if you just swallow it as we are missing something called  the "Intrensic Factor"

[UA13]

Thanks everyone.

The doctor didn't really tell me how low it was, and he didn't suggest anemia, but said it was "a little low". My tsh was also elevated a little (it's been staying pretty elevated since I started feeling awful), but he didn't want to put me on thyroid meds.

I'm really not sure why my B12 is low. I'm a 29 year old man, I was eating pretty well and regular prior to getting sick, but now I'm just a wreck.

Yesterday after I had the shot, I didn't feel anything but a little more tired than normal. Today, I absolutely crashed. I felt awful. I couldn't think clearly, I was so tired I could barely walk, and just overall felt horrible. I had 1000mcg of sublingual b12 about an hour ago, also. The doctor told me to take b12 supplements, so I'm starting now.

I'd just always heard that as soon as you got a b12 shot, you almost instantly felt more energetic and ready to go. Some people said it took a few days, though. I certainly haven't felt anything other than more tired. I hope it passes soon.

[UA13]

Oh and one more question. I've been dealing with this for 7 months, and the brain fog is horrible and the fatigue is, too. Will the brain fog go away after b12 treatment for a while? It is absolutely horrible to deal with.

[Londres70]

The b12 should also help the brainfog.  Keep an eye on the situation with you TSH/thyroid.  Problems with your thyroid can cause brain fog too and other symptoms as well.  Your physician might need to medicate you for the thyroid problem as well.  

Sounds like you are young and take care of yourself, but sometimes these things run in families.  

[SassyLassie]

Keep doing the shots, in some folks, it takes a while to work. I took them for awhile and I felt great, gave me a lot of energy, but, after the initial "boost" wore off, and my body got used to it being in my system, the results were not that remarkable. Also, take a good "B" complex this will help the shot to work better too.

I have a lot of brain fog, but, mine is due to peri-menopause, so, that does not concern the problems you are having :-), I take a minute dose of natural thyroid, it helps some.

[UA13]

My TSH has been going up and down for the last 6 months or so, usually going from 2.0 - 4.5 or so. Last time it was checked, it was 2.3. Doctor said he didn't want to put me on thyroid meds though, because it was "normal".

I certainly hope the b12 works. It seems to make me feel worse when it starts working. I get so worn out and nauseated.

[UA13]

You mean the raw thyroid stuff? I thought about trying it, but was a little worried about it. Does it help you any?

I was curious if my thyroid might be causing my b12 to be low, or if my b12 could be causing my TSH to go up.

[SassyLassie]

I have taken the raw thyroid, it did not do a lot, what I am taking is a prescription from a compounding pharmacy, it is similar to the drugs, but does not have the side effects, it works pretty well and I notice that if I skip a day or two of it, I get really irritable.

Yes, the thyroid could be causing the low b-12, or, the low b-12 could be causing thyroid symtpoms, they are similar.

[UA13]

Thank you! Just wondering, 'cause since I started taking the B12, I actually feel WORSE than I normally do. I'm hoping it will subside after a little while, because this is making life even more difficult.

I suppose I should get anemia ruled out, to determine whether or not it's my thyroid affecting b12 or vice versa.