I know you have probably heard every remedy in the book and can't just run to Walgreen's for another, but just in case....ginger capsules. They work wonders for me. I can read while sitting sideways in the back seat of a car that's winding through the mountains of West Virginia and not feel the least bit of motion sickness. Love it! I've not sailed, so I'm sure it's much more profound, but still worth offering the suggestion. I'll pray that the waves quit thundering around your bunk!