[Ellie F]

Hi Valerie and welcome.
I feel herceptin does increase fatigue and I think a number of others will add their thoughts to.
Just wanted to respond to your comment that you had been very well, no flu or colds for a long time before you got breast cancer. This was exactly the same for myself. Interestingly at my last onc appointment a research nurse told me that some cancer researchers think that as the immune system has not been 'triggered' for a long time it in some way loses it's ability to detect and destroy rogue cells and cancer develops.
Makes you think.
Cheers Ellie