StormJib said:
There is no magic instant pill or device. Find what works for you and start using it in advance of any motion.
This is the main thing to realize. There is no magic pill. What works for one person may--or may not--work for another. Anyone who tells you "this is what I take and it is guaranteed to work" is simply wrong. It works for them. Great. Does not guarantee that it will work for you.
The good news is that pharmacies in the islands can generally sell you a variety of things that would require a prescription in the United States. Pick one of the suggestions here and try it out (meclizine works for me). If it works for you, wonderful. If it doesn't, stop in at a pharmacy and talk to the pharmacists. Tell them what you have tried and they will probably be able to suggest something else that might work better.
Good luck!
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