Full ears & post nasal drip for over 2 years,my new dr said allergies.. im having hard time eating and swallowing from post nasal drip. what can i do?

Post nasal drip(PND): Did he recommend antihistamines or nasal spray? Would f/u w/ allergist for food allergy testing or try avoiding milk products for a week as they sometimes are associated with sinusitis/ PND. Also at times reflux can result in sinus irritation and PND. Would elevate head of bed when sleeping , try ranitidine if not allergic and zyrtec -see if helps and f/u w/ allergist.