u&iraok, Those are all good bitter herbs. Out of that list, I like Olive Leaf Extract best from that list and have taken it for many years, whenever I have viral symptoms. Seems to have anti-viral properties, and helps me sleep better when I take it at night. Oregano, GSE, Olive Leaf Extract, and Colloid Silver, those are the ones that have helped me the most, also sometimes garlic. But ginger is good for calming an upset stomach, and eucalyptus of course for nasal inflammation.