Bubbletrubble
Contributor
Allergies are one thing. You can take an OTC antihistamine to prevent them from becoming an issue while diving or during air travel. I'm not so sure I would recommend taking a systemic decongestant, such as pseudoephedrine (Sudafed), to deal with recurring allergies, though. Sudafed does have some potentially serious side effects that you should be aware of before taking it on a dive trip.I DO have pretty bad allergies so I will look into the sudafed before diving. This should help clear those passages. There are times when I'm even on a plane and can't equalize my ears, so this might be a problem I have before each dive.
It's possible that you could have a certain amount of Eustachian tube dyfunction. An ENT might be able to figure out the root cause of the problem.
Best of luck with everything...