Haven't been pukey seasick ever! I sometimes get drowsy from the prolonged several days, weeks, of ocean motion. I do my darndest to keep my belly full when the ocean is rough. I agree with Bodo to an extent that it is somewhat mind over matter. If you think you're going to get sick, you will. BUT it doesn't necessarily work the other way. I love the heavy greasy breakfasts before a trip or on a boat! Keep your head up even if you take the meds, inner ear.
Find what works for you and use that!
The first preventative for seasickness that I was told about, back when I was in high school, 1980ish, smoking pot and drinking Perrier!
If ya got one of those medical marijuana chits, give it a shot, it certainly can't hurt unless you are driving the boat! Maybe it was just the munchies that kept our bellies full back then..
... I haven't tried it in over 30 years..