My surgeon requires you to stop drinking all caffeine prior to surgery, and none after surgery for several weeks. Giving up caffeine was one of the hardest things I've done! I used to drink a 20oz black coffee in am and 40-60oz of Diet Coke a day! I took one week to reduce that and then stopped completely. The headaches were horrible! I was moody and sleepy all the time. I was in bed everynight for that first week by 8pm. It was terrible!
But...let me tell you how much better I feel now! I used to blame not sleeping well at night on being a Mom and listening for my kids during the night. I now know that it was the caffeine. I used to wake up 4-5 times a night when drinking caffeine. I never had problems falling asleep, just staying asleep. Not anymore though, I now sleep through the night. Also, if I didn't have caffeine in by 10am at the latest, I would get a really bad headache. Not anymore! Even after surgery I will never go back to drinking caffeine. It's just too addictive for me. Trust me, if I can stop drinking it, so can you. It's one of the hardest things I've done, but just set your mind to it and do it!