Taking Corticosteroids And Antihistamine For Chronic Cough. Side Effects Of Prolonged Usage?

Question : My mother is 46 yrs old. last november she had fever and chills and developed a cough that wont go away. did blood tests everythin was normal. xray was normal too.. did a chest ct. ct was normal.he was using salbuterol inhaler for a while and the cough seemed to have reduced. again in XXXXXXX dis year she developed the same cough did a lung function test and sinus ct it was too normal. the doctor said the cough might be due to allergies since i have parakeets and budgies at home. he gave a nasal spray. little cough was still der. it was not perfectly gone. then again we went to another doctor who gave a inhaler(forocort 100)stating peak flow was ok. cough got reduced for the next 2 months but this month she started coughin a lil too much than before. we did a skin prick test. peak flow was ok and saturation too was 70 she seemed allergic to molds(3mm)dust mites(4mm) dog epithelia and cat dander(3mm)mosquitoes and cockroach(3mm). but there was no allergen test for birds.. dostor prescribed forocort 200 for 1 month and ebast 10 mg and synasma 400mg for 5 days and defort 30 mg half tablet for 4 days. we have been having parrots for 3 yrs and she developed this cough last year only. since the doctors visit 3 days she did not cough but when taken this tablet and forocort she complains of chest pain and chest burn. is it only due to allergy or somethin else. my mother is scheduled for another spiromety. after 4 weeks. is their any side effects of prolonged usage of corticosteroids and antihistamine. she is also takin stamlo 2.5 mg. provided there is no way we can get rid of birds(parakeets and budgies)