Occasionally at night while sleeping I have a dry cough

So occasionally (not ever day) I will have a dry cough while sleeping which is sometimes associated with difficulty catching my breath. At times when I exhale I can make myself wheeze as if I had asthma. I am a smoker of 1 pack per day and except for an occasional cold and being overweight am healthy. What could be causing this? Do I need to have any tests done? Thanks.

[National Jewish]

Since your cough is continuing you need to see your doctor.  This is especially important for people who are heavy smokers and even more important for those who are over 40 years old.  A chest x-ray will generally find the serious causes of your cough.  The most likely cause of your occasional dry cough while sleeping is irritation of the airways of your lungs from smoking.  Perhaps this is combined with breathing dry air through your mouth during sleep.  Your cough could also be due to other health problems, such as heartburn, postnasal drip, or sinus problems.