Hi Kathy,
You might want to read the thread on wierd things happening on Herceptin, but in general, after the first tx when they will give you Benadryl and Tylenol as a premed, you won't have any premed and you will feel just fine afterwards. You may be sleepy from the Benadryl the first time. There are others that have slight flu symptoms, and still others that are allergic to it. It seems that some that did not react well to it, had the fluid that was mixed with the Herceptin changed and this heipled them tolerate it.
I do not expect you to have any problem with it and except maybe for the first infusion, you will probably work with no problem. And no losing hair! Not with just Herceptin. Your mileage may very, but this drug was very gentle with me and I react to everything!
Here is on of the links for those that had trouble with it.
http://her2support.org/vbulletin/showthread.php?t=27118
Hugs,