If i have a non-productive cough, what could it be?

Possibilities....: There are many possible causes of a non-productive cough including throat irritation, bronchospasm, medication side effect, post-nasal drip, GERD, etc. In turn, there are many conditions that can cause bronchospasm like asthma, COPD, CHF, etc. Treatment depends on the diagnosis so see your doctor so that your cough can be diagnosed and treated.