It depends on the severity of the congestion. Many people have flown with a mild case of congestion and have had no major side effects of complications to the extent of what the above poster has experienced, I being one of them. It is a given during the winter months when living in certain parts of the country that you will at some point experience some sort of congestion and or a minor cold.
Ear pain associated with flying is simply due to unequal pressure between your middle ear and the cabin of the airplane. Normally, the eustachian tube, which connects your middle ear to the back of your nose and throat, equalizes the pressure. But if the tube is blocked because of congestion or some other problem, the unequal pressure on your eardrum may impair your hearing and cause ringing in your ear (tinnitus), dizziness and ear pain. If the eustachian tube is completely blocked, pressure changes may be severe enough to cause fluid buildup, ruptured capillaries and bleeding in your middle ear. Certain nasal sprays seem to work when I am congested and flying.
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