Tessalon and night time coughing

My doctor prescribed Tessalon because I can't stop coughing long enough to sleep. I used it last night and it helped for about 3 hours. He said to take it 3 times a day, but is that breakfast lunch and diner? Or should I be taking it before bed and again as needed in the middle of the night? I don't care if I cough as much during the day its the night coughing that is preventing me from sleeping. Any one else used this medication?

Dazy,
Razzle is correct in telling you to call your physician.
I just looked at my prescription which is for 200 mg., which is a high dose, and my allergist says take one capsule every eight hours as needed. We are all so different. When I get bronchitis, it can get out of hand fast and that is what my allergist is trying to ward off.
Especially since tomorrow is Friday and you probably can't get in touch with anyone over the weekend, I would advise you to go ahead and call your doctor's office tomorrow.
Feel better!
Carla