I cannot give any advice on interactions. It is hugely complex, huge amounts are not known and I am just an amateur bringing the work of others to peoples attention. It is best to talk to your onc. Blood thinning is a known issue and rare conditions.
I have seen trials suggesting that herceptin intervenes in the fat pathways as one of its effects. Exactly how and to what extent that is a question I cannot answer. I have not seen any trials of DHA EPA omega three as an adjunct to Herceptin, but have not searched recently.
As to brands a good brand with high levels of DHA and EPA that is distilled or checked for contaminants. Somebody posted a link to a site that gave a list of suppliers. Here is another
http://209.85.135.104/search?q=cache...ient=firefox-a
Bottled is cheaper. Here a re a couple of links but do check locally etc.
http://www.vitacost.com/NSI-Liquid-P...mega-3-EPA-DHA
They also sell Carlsons in bottles but the ingredients seem fairly similar but please check for yourself.
Come back if you need any more info. I will try and help with links etc if I can. IF you do go down this route after discussion with your onc etc please let us know if it appears to have helped or not.
The "Greek Diet" post has some material that might be of interest to your onc.
RB