Thanks for writing in.
Such a symptom can occur with what is known as 'Diabetic Gastroparesis'. You can do a couple of things ... just check your blood sugars during such an episode with a glucometer. Generally we dont expect Januvia
to cause a drop in blood sugars however sometimes some people do have certain undefined symptoms with sugar fluctuations.
The second thing you must do is try eating a little early before bedtime. If these donot help we may require to start on some prokinetic agent which will surely help. You can consult your local doctor for a prescription for the same.
Hope I have answered your query. If you have any further questions I will be happy to help
Dr. Om Lakhani
http://www.healthcaremagic.com/doctors/dr-om-lakhani/60313 (online expert diabetes