The Ear pain
& muffled hearing while travelling in a plane during ascending or descending is due to sudden variation in the external pressure leading to ear drum stretch & injury
. Also due to movement of fluid in the middle ear to balance the external pressure. For those who have sinus
the symptoms will be more because of existing congestion. Oral Antihistamine & decongestants prior to travel, Plucking of ear during ascending or descending, drinking of water once the symptoms occur may help to relive the symptoms. The same external pressure variation occurs during climbing up or down the mountain by a car.Take precautions.