I am a 69 year old man with chronic daily headaches since Last fall. They started right after I had an arthroscopic surgery done on my knee. I've seen a neurologist and had a negative MRI. Several years ago I had a mini stroke from which I recovered immediately. Last summer 2011, I had an episode of possible menningitis which resolved with antibiotics before they could get a spinal tap, which couldn't be done immediately because of two previous back surgeries that made it necessary to do it under fluroscopy guidance. I am in good general health. After having a total shoulder replacement this summer, I have gradually removed almost all my medications such as an antiinflamiatory, Tylenol and Tramadol (Ultram) for pain, and a muscle relaxant. Doctors have tried to find a blood pressure medication that doesn't cause headaches to no avail. The headaches are the worst I've ever had, have rapid onset, occur usually on one side of my head, but leaving my head tender all over. They last several hours and slowly resolve. Heat occasionally helps some. The headaches leave me very grouchy, but I am usually cheerful. Any ideas?