To prevent motion sickness and vomiting, you can use over-the-counter antihistamines like dimenhydrinate or meclizine, taken 30 to 60 minutes before you travel. Please note these can cause drowsiness. For longer journeys, a prescription scopolamine patch applied behind the ear four hours before travel is highly effective. If you prefer non-drowsy or natural options, ginger tablets or acupressure wristbands can also help. For severe symptoms, a doctor can prescribe stronger anti-nausea medications like ondansetron. Always consult a pharmacist or doctor before starting a new medication to ensure it is safe for you.