Natural Remedies: Some people find that peppermint or ginger are beneficial in reducing nausea. To stop motion sickness from getting worse, try rolling down the window, taking deep breaths, and overthecounter (OTC) meds if necessary.The following strategies can help you avoid or lessen motion sickness. Sit in the front of a car or bus. INCREASE VENTILATION: When motion sickness symptoms start to arise, getting fresh air can help ease your symptoms. Promethazine. Promethazine is a prescription antihistamine drug used to treat motion sickness. People with motion sickness commonly experience dizziness; headache; nausea, vomiting, or retching; sweating. Buy some dimenhydrinate tablets (such as Dramamine) at your drug store. No prescription is needed. Riders can make reservations up to 7 days prior to a trip, but must make each trip appointment at least the day before traveling.