I've Had A Cough For The Last 5 Weeks That

I've had a cough for the last 5 weeks that just won't go away, I've gone to a local clinic and they prescribed Zpack even though they found nothing. I've actually blacked a few times from coughing so hard, I don't have chills, what I spit out is clear. I don't feel sick at all, it's just an annoying chronic cough