Hello. Usually pneumonia take two weeks for recovery and resolve within this period. Initially you took Zpac and thereafter Doxycycline ,still cough present .Cough is associated with expectoration ( phlegm) i.e.infection still present or allergy.May be due to . 1 Either pneumonia does not resolve or due to allergic bronchitis .Diagnosis can be confirmed by physical examination including X ray ( as usually we find resolved lesions in X ray) . 2 Bronchiectasis , usually I have seen that huge amount of expectoration is due to bronchiectasis and this is very common after pneumonia . Diagnosis can be confirmed by sputum examination with clinical history. 3 Tuberculosis , usually this is very common among pneumonia patient .So get in sputum , X ray chest , blood for E S R . In my opinion you must consult another specialist pulmonologist and get his ( 2nd) opinion as above mentioned . Although now a days doctor do not consider E S R as any important parameter but in my opinion ,if E S R is very high ( 100 mm 1st hour ) it is specific and an indication of serious chronic infection , so get in blood for it. Good luck. Dr. HET