Letrozole and fatigue

Thiamine is not looking a wise supplement choice as is a suggestion causes tumour growth but did also note anaemia often a problem with some bc treatment eg chemo @Cyclo whilst I don't have headache - should I say yet as am only 7 plus weeks in -  which is another Letrozole side effect  if I "overdo it " ie live my life at my normal pace -  I too end up exhausted. - fatigue also effects my thinking and I feel a lot less able to juggle what I used to .The web site breastcancer.org covers the common side effects http://www.breastcancer.org/treatment/druglist/femara  . I think exercise for all of us might be very important on this drug but we are going to have to pace ourselves and maybe accept going slower than we would like - I do feel better after an hour walk  -must be getting more oxygen into the bloodstream .I too only had radiotherapy but experienced major fatigue after it ended for a week . I wonder if this is a side effect of letrozole that eases over time .Kath has been on it 12 months but has had chemo which also causes fatigue - wonder if anyone on here has been on it for a while and found fatigue has eased ?