Cold like symptoms for a year

my dad has something like a cold for the past year now. Everytime he goes to the doctor here they tell him he has a cold or an allergy and gives him antibiotics WITHOUT any significant tests that might indicate or find the reason of why he's been coughing a lot for the past year. My dad has no history of asthma nor smoking. Shouldn't they have at least taken an x-ray, sputum sample or maybe even a bronchoscopy? i don't understand why they resort for him take take antibiotics right away and on the other hand these antibiotics are heavy on the pocket; without having any positive output.

Please help.

[Enoch Choi, MD]

a year of cough deserves an Xray of the chest, perhaps a cat scan, and if either of those show something suspicious, then bronchoscopy may be indicated.