I had a severe case of this when I sailed from Vancouver to Hawaii. I think there were 5 or 6 sea days in a row, and some choppy seas the first couple of days. On my first port day I felt like I could barely walk on land! I called my brother who was a commercial fisherman, and asked for advice. He advised me to eat something salty, drink something cold like ginger ale, and sit down or lie down with my eyes closed for a few minutes until the feeling passed. I tried it and it did help. Each episode thereafter I did the eyes closed and lie down if possible, and each time got a bit better. Now before and on each day of sailing I take one Sudafed (little red pills) and it seems to help my inner ear. Good luck!