Ginger tea

What is the best time to take ginger tea for all day sickness? First thing when you wake up, empty stomach? Or mid day?

I have just got these nice twinnings lemon and ginger tea. Was wondering when it could be most effective.

I have sickness the whole day, throw up occasionally. I get a constant heavy feeling in my stomach the whole day. Plus now when I vomit it's quite violent, like my stomach keeps contracting like crazy till it empties.