Are you harming your vocal cords?  

 According to
Throat Clearing & Harsh Coughing
Throat clearing and harsh coughing are traumatic to the vocal cords and should be reduced as much as possible. One of the most frequent causes for throat clearing and coughing is thick mucus (due to dry vocal folds) or too much mucus (as with a cold) on or below the vocal folds. The safest and most efficient way to clear mucus is by using a gentle, breathy productive cough where there is high airflow with little sound. This can be achieved by using the following strategy: take in as deep a breath as possible, momentarily hold your breath, and produce a sharp, silent “H” sound while you expel the air.
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