I have a severe sinus infection and bronchial cough. Zpac did not help. Dr. prescribed this... 300mg, 3x's per day. I always take meds. with food and I drink a full glass of water. I've been having such disturbing nightmares --- to the point that i wake with severe neck and head pain along with sore jaw (prob., from grinding teeth). I should note that I have anxiety/panic attacks for awhile and on prozac 20mg (which has helped tremendously) for the past year. Also, while taking clindamycin, I have had such diarrhea, especially in the mornings. Is any of this typical with antibiotics (as my friend had nightmares when taking zpac) or is it all a bad side effect? Thank you for any help you can provide for me.