Ear pain and discomfort, or vertigo (dizziness), from air pressure changes during flights is a common problem. Ear pain will be increased and can be excruciating if suffering with Cold/Flu, blocked sinuses, ear infections or allergies.
The extra ear pain associated with cold/flu is due to congestion and blockage of the eustachian tubes. The eustachian tubes are located between the back of the throat and the inner side of your ear drum (middle ear) and help the ear cope with pressure changes.
Do Not Fly With a Cold: This is the easiest way to avoid ear pain. If possible, delay the flight until after you have recovered from the cold/flu. This will help save other people from catching your virus in the air conditioned environment of a plane.
Take a decongestant: A decongestant may be able to reduce your discomfort from ear pain by shrinking membranes in your ears and sinuses.
Avoid Milk Products: Milk products up to two days before a flight are reported to increase mucus production.
Chew Gum, Swallow, Yawning, Crying, Pressure on the back of the tongue: These techniques will often give full or partial relief from ear pain and can repeated as necessary. They are also free. Crying is best left to babies on the plane. Getting babies or young children to drink promotes movement that may reduce ear pain.
Blow Gently While Holding Your Nose And Keeping Your Mouth Closed: Do not blow too hard as you may damage your ears. If you hear a popping sound, you have succeeded and your ear pain should now be relieved.
Ear Planes Ear Plugs: Ear Planes are special ear plugs designed to reduce ear pain from pressure changes. They have a pressure filter that reduces the rate of change and were originally developed for Air Force pilots.
Half a glass of water covering the ear: I once saw a flight attendant give a passenger half a glass of water that she put near her ear. Not sure if this works though, as when I tried to get a glass on my last flight I was promptly told from the stewardess that the flight was landing. On a second attempt (opening my mouth) just to ask for a glass, I was once again told the flight was landing (she had not even announced it yet). If Air Asia were more precise about some of their other practices, maybe more of their flights might leave on time.