Julleri, I have all the same symptoms as you do. My story is long. I'm hypersensitive to everything, many allergies, etc. I wiegh 90 lbs, psoriatic arthritis, small bowel obstructions, have been b12 deficient for yrs, but discovered 7 months ago when I realized I didn't feel like I was dying when I ate GrapeNuts cereial..I realized I had never had a B12 source...never. I've had many intestinal surgeries. I've been working with my neuro, allergist, rheum, gastro and internist docs. 1500 mcgs/1 dose worked miracles and about killed me. First thought it was additives, witch it was, but after switching to nothing but methylcobalamin and water by Bio-Alternatives..online co. I switched and use Pure Encapsulations Methylcobalamin. I get it from my pharm but can be found online to buy. This is the one my docs recommend.

None of my docs would attempt the injections for fear of an uncontrolled reaction. Liiqiuid sublingual was deemed the safest for me.

There are nerve pathways under the tongue that readily accept the methylcobalamin and send it directly to the spine and then on to where the b12 is needed. I was told this is my best hope of repairing my memory and pain.

Methyl is the type of b12 you need to use because is works best for neurological problems. My 5 yr neck pain, level 10 is alleviated when I am able to take enough. I am allergic to cobalt. I cough constantly when taking the several doses of 20mcg...yes, mcg not mg...NOT the case for most. I'm hypersensitive and that small amt is keeping me alive with some benefits. After that first 1500, I used 1000mcg for a couple weeks, then 750mcg, then 500mcg..was taken off the b12, my cough and other side effects stopped the next day...back on at 200, then 100, then down to 10mcg per day. I am trying to desensitize my immune system to the cobalt. I can tollerate 60mcg now but...new hernia at my sternum from the cough...lovely.

So, point is, everyone is different...yes, I feel crazed with too much, yes, hard to breath, eyesight blurry, feel like you're dying, everything,..my hands can't feel eachother. But, I am so darned sensitive that the b12methly has restored most of my memory. I can read again, can think quickly...motivated. for 2 weeks I had leg and feet pains, then moved to my arms and hands..this pain is from nerves regenerating, I was told by my Neuro. B12 supports the myelin that covers the nerves.It's padding so they don't get frayed, sort of.

Sorry this is so long...wanted you to think even harder for a reason you can't tollerate this vitamin. Is it the preservatives, additives, is it too much at one time, taken at the wrong time for you??? It's taken months for several docs and myself to come close to my answer and we're not there yet. ...so frustrating.... good luck to you..

deb...