Take preventive medicine
before the journey begins, since it works better than taking it after nausea has started. First-generation antihistamines and scopolamine are the main effective options; non-drowsy allergy medicines such as cetirizine, loratadine, and fexofenadine generally do
not prevent motion sickness. The
CDC motion-sickness guidance supports these choices.
Also help prevent symptoms by sitting where motion is least felt, looking at the horizon, getting fresh air, and avoiding heavy meals and alcohol before travel.