As a doctor, one of the first questions I would ask your husband: "Do you smoke?"
Coughing can be due to a number of conditions and each condition may have a distinct history pattern which can help the doctor sort out a diagnosis. For example, the duration of the coughing history can be important since a chronic cough for months or years will suggest one cluster of possible diagnoses where as a cough for a week or two suggests other diagnoses. Whether the cough is productive of sputum and of what description is also of importance. The presence or absence of shortness of breath and if present under what conditions does the cough or shortness of breath occur. The significance of these symptoms at rest vs associated with exertion is different. The presence of other symptoms including whether loss of appetite or weight loss or chronic fevers or night sweats are also important for diagnosis. And there is more and more questions which should be disclosed by the patient or questioned by the doctor. Did you notice that I didn't present any diagnoses associated with these historical possibilities in my commentary above? That's because there is a lot more to think about from a statement "my husband is always coughing" and I didn't want to suggest diagnoses on Medpedia when if the cause of the cough is unknown by the patient or his wife.. guess what? It may be, as suggested above by Kerri, time to see the doctor to help make the proper diagnosis. ..Maurice.