I have very hypersensitive lungs and diagnosed asthma. i've had post nasal drip and sinus irritation for months which is aggravating my asthma. meds?

SInus and Asthma: It is not unusual to have nasal/sinus problems combined with asthma; the cellular changes affecting the nasal passages and bronchial tubes are similar. While a number of medications may help PND and other nasal symptoms (intranasal and oral antihistamines, decongestants and intranasal steroids) an evaluation to determine the underlying cause (allergy, polyps etc) will allow more specific therapy.

Post nasal drip: Yes there are likely meds that will help but you should speak to the person managing your asthma and consider an ENT evaluation.