No sleep at night

Patient: My wife age 41 has come on a visit from India to Kuwait. She is staying here for last 1.5 months. For the last one week, she has the following problemShe is unable to sleep in the night due to repeated cough. She feels her tongue is getting dry repeatedly and drinks lot of water in the night.In the day time she doesnot have any problem. We had contacted a physician and did a blood check but no specific problem noticed.Could you inform what may be the probable reason for this behavior? My wife is slightly obese and Kuwait is having dust storm these days. Whether these could be the factors?

Doctor: