The solution is oral scopolamine!!!
It comes in 3 microgram doses and I often take half or a quarter of the pill. It is chewable- I usually chew it a bit and put it under my tongue. I was introduced to it on a Mike Ball liveaboard in Australia and have never looked back- the patch doesn't control the dose, and I don't feel comfortable diving (I'm usually guiding or instructing) with how Dramamine makes me feel.
The oral scopolamine has made me feel better when I'm already sick.
It used to be available by prescription in the US, but big pharma has done away with that. It's available over the counter (and quite cheap) in the UK and Australia. Not sure about Canada or Europe.
Everyone with whom I share it has agreed- it's a miracle! If you get the chance, please try.
Hyoscine