From Visit 1 onwards until the end of treatment you are allowed to use dimenhydrinate (e.g., Vomex® alternatively, cyclizine or meclozine) as rescue medication to reduce your symptoms, if it is used in the standard prescribed dose and not applied more than 2 days per week. Because intake of rescue medication might have an impact on study results, you will be asked to document each intake of rescue medication in the patient diary on a daily basis.