Many thanks to you three for the suggestions. I think that in the name of preparation, I'll do them all and hope for the best.
The methods and medicines we have available to us now made me wonder, what would Russell have done had she the same access we do to them? I just can't see her popping a pill, due to her history. Having spent a little time in Japan, she might try the acupuncture pressure. I can see her being just stubborn enough to suffer the voyage unaided. :-)