Dimenhydrinate (marketed under brand names Dramamine, Gravol, Gravamin, and Vertirosan)'s an over-the-counter drug used to prevent nausea and motion sickness. It's marketed in Portugal as Viabom, but in prescription format. It's most commonly used as pills, although it's also available in liquid form and in suppositories. This last's particularly useful in the case of persistent vomiting. It's closely related to diphenhydramine HCl, or Benadryl. The differences relate to the weight-for-weight p… (More on Dimenhydrinate)