My husband is having a cough(starting dry then wet with mucus stuck)for which he got treatment for 10 days in which antibiotic given roxid 150 mg 2 times a day for 5 days doxycycline 100 mg 5 days plus cough syrup and some anti allergy drugs. now after 10 days the cough is very much controlled but after a gap of 3 days cough is started again. the area in which we live is delhi. there for lot of pollution. now another dictor gives Azithromycin 500 two times a day for 5 days. my query is that as it is everywhere, the Azithromycin 500 can be given 1 time for 3 days ir 5 days. so why does the doctor give 2 times a day. also it looks the cough is from some allergy reasons. there is mucus but not so much nor ao thick it is white. no fever no chest pain.