We are soon to be going to France by ferry and my DH was 'once' seasick on a boat a very long time ago. Then drummed into him that he is seasick by his mother! He is now really worried this will happen again. So what do people recommend to take or do to prevent it if it does occur again. We have been on an hour crossing before and he was fine, but this one is four hours and I think he is nervous. Bands? Tablets? Thanks in advance!