Your symptoms of post nasal drip
, dry and itchy throat, possible nasal obstruction
is likely to be related to house dust mite allergy
. It is of course possible that you have pther allergies such as to grass or tree pollens, animal dander (especially if you have pets).
You therefore need to get either blood tests (specific IgE) or skin prick tests to exclude these allergies.
if proven dust mite allergy, winter (western countries) and rainy seasons are worst due to increased humidity. Long acting non-sedative antihistamines like allegra 180mg ad nasonex 1 spray per nostril
once daily are required for a 3-month duration to see the effect.
If you fail optimal therapy, you will need immunotherapy
but that would depend on the number of allergies you have.
I hope that helps.