This may be completely irrelevant, but I read recently an article by a gastroenterologist whose patient complained of acid reflux. The doctor asked her several questions, among them, "do you use peppermint, by any chance, to relieve the symptoms?" She was astounded and said, "yes, frequently."
She was advised to stop them because they cause more trouble than they do to provide help. The physician said that peppermint causes the muscles to relax somewhat making acid reflux more likely to occur. Without using them, the lady improved remarkably within a very short time.
As I indicated, this may be completely irrelevant to your problem, but worth mentioning just in case you try to self-medicate.
Another route to follow might be that of having an allergist check for mold allergies (since it's worse in winter) or allergens in the home such as minute dust particles or dust mites (which all homes have, no matter how clean).
Good wishes on finding the problem.
Post Edited (It's Genetic) : 2/16/2012 2:10:37 PM (GMT-7)