Chronic Coughing at Night?

Ok so for the past 6 days or so I've had extreme coughing fits at night.. just like clock work.. I went to the DR friday who told me I have bronchitis - prescribed me antibiotics and prescription cough syrup.. i started the medication right away. WELL low and behold I'm still having these out of control coughing fits at night.. a really dry non productive cough.. I've maybe slept 10 hours altogether since Friday.. any advice??????? The cough syrup is not helpful at all.. my mom had a stronger prescription cough syrup and thats not helping me either.. any advice would be greatly appreciated