When I had my bloods done last year after complaining of leg/arm pains I was given a course of Vit D tablets as levels low. I felt great after a few weeks, pains went, nails grew fabulously etc. 6 months later I am again having awful pains, nails have gone, breaking flaking etc and hair falls out, v. tired etc. When I was given the Vit D tablets I was told that I would only be given 1 sharp dose. Can you only take them once? I have tried supplements of Vit D from local chemist etc but still suffering with leg/arm pains, tiredness etc. Any advice please would be appreciated before I go back to GP in a couple of weeks. I take 100mcg of thyroxine daily.