I get asked regularly if Vulcan Silver is effective against the flu and the simple answer is YES! However, prevention is better than cure and I recommend that those who can should drink at least 1ml (20drops) in a small glass of water (50ml will be fine) and on an empty stomach as a prophylactic against day to day nasty's. In the five years that I have been drinking Vulcan Silver daily I have not taken a day off work due to illness including the flu. However should you feel the onset of flu i.e. sore or scratchy throat, runny nose etc. then start a regimen of 2.5ml (50 drops) three times a day on an empty stomach and continue for at least four days even when the symptoms abate. It is very important to catch the flu before it takes hold of your system otherwise recovery, even with Vulcan Silver, will take about seven days.