Oh yes, I am most definitely ad very uncomfortably suffering from cold so you are suffering from a barrage of cold related posts. Yeah, I stick to Eucalyptus Oil during cold but I didn't try taking bath with it ever. So, try this out. Let out really hot water (which might make your skin dry), add a tablespoon of eucalyptus oil to a bucket of water (change the proportions accordingly) and take bath with it. Make sure you bathe in really hot water. It will give immense relief and the experience is even better when the water is steaming hot so it releases eucalyptus oil vapors. Your bathroom will smell of the oil for hours later on and it will give a little bit of relief surely. Otherwise, taking bath while having cold feels really tiring.