I will be doing a wreck dive off the NC coast next month . One of the wrecks is a 2 1/2 hour boat ride to the dive site . I've never been sea sick , but have seen divers that got sick and its not a pretty sight . I'm thinking about taking medication with me . I understand that Scopolamine patches work well but need to be taken 4 hours before getting on the boat . I would prefer to take medication only if needed , maybe compazine or phenergan . How would these medications affect a diver ? I think all say they can cause drowsiness .