It may be a good idea, just in case, to ask your health care provider about which medications are safe for you to carry along to calm seasickness. Seasickness bands are useful for some people, although there is little scientific evidence that they work. These bands use acupressure to help ward off an upset stomach.
Another concern for cruise ship passengers is norovirus infection. Noroviruses are a group of viruses that can cause severe nausea and vomiting for 1 or 2 days. They are very contagious and can spread rapidly throughout cruise ships. People can become infected by eating food, drinking liquids, or touching surfaces that are contaminated with the virus. Before you book a cruise, you may want to check whether your ship has passed a health and safety inspection conducted by the Centers for Disease Control and Prevention (CDC).