Is meva c used for long term? Get freed!

Hi sir/madam, 3 years back my brother has vitamin d deficiency and was diagonosed he has ileocical TB and he started TB tablets after 6 months suddenly one day fron toes to stomach he got pins and needles and tingling sensation and we stop TB tablets after 8 months during that ATT he took B long tablet for two months only and he stopped he doesn't ate non veg at that time since from 6 years he not ate non veg and after that we consult doctors and his vitamin b12 also low levels and they give tablets and my brother takes that tablets for about 1 and 1/2 year slowly the tablets  working but full recover is not there  then we go to nasal spray but not worked after that we went for b12 injections he got side effects like brain fog mood change stomach upset and muscles cramps in legs hands and stomach right leg got effected and he take pantop 40mg injection and meva c recently he take homeopathy and that agrevated bloating and he always burping  and when he burps that leg also get freed