One is called Coldcalm. It's by Boiron, who also make Oscillococcinum and Chestal (for kids). You can use any of those products, even while nursing.
You can also use any Tylenol product, just like you can while pregnant. Another recommended brand is Zicam. They are all safe while breastfeeding.
You can also, of course, use natural remedies. Things that are herbal. Before doing anything, though, if you want to be cautious, check with your doctor and they can give you the best idea of what you can safely take while nursing to get better.