anxiety
"I was prescribed Klonopin for anxiety several months ago. The dose was 0.5 mg up to twice daily.  Never having had it, I quartered a 0.5 mg tablet first dose. Seemed okay until a few hours later and I began coughing like mad. I have asthma.  Klonopin made me cough and increased the thickness of the mucus in my lungs until it was almost impossible to cough it up.  Just to be SURE it was the Klonopin and not something else, I have given it two other tries 1/4 of a 0.5 mg tablet.  Each time the same results.  I looked it up and "cough" is the 2nd most common side effect. FYI Naproxen and ibuprofen have the same effect on me."