Have you tried a detox bath? This simple recipe makes a great base for adding essential oils. My favorite blend for a cold/flu: eucalyptus radiata and white fir. If you have the starter kit these are couple of great mixes: lavender and peace & calming or lavender, lemon and peppermint. You can even add some ground ginger if you're trying to really sweat out some toxins.
Make sure you mix the epsom salt, baking soda, and essential oils separately before adding them to your bath. It's best to let them soak for at least 10 minutes. Enjoy!