I have also had adrenaline spikes which wake me up every morning for at least the last 18 months. I have seen a primary care doctor, a psychiatrist, a sleep specialist, a neurologist, and a spine doctor ( I was having some back problems also). I have had many blood tests, an MRI, and a sleep test. The only doctor who suggested a possible explanation which feels right to me was, oddly enough, the spine doctor. She said that my blood pressure might be dropping while asleep (I guess this is normal when we sleep) and my body was over-compensating with the rush of adrenaline. I am on a small dose of Zoloft, and the neurologist prescribed Clonazepam, which hasn't helped much and I don't like being on a benzo, so I hope to discontinue it. I have been waking up at 3 or 4 am lately, so am feeling very sleep-deprived and would like to figure out how to calm down the adrenaline. Meditation and exercise relax me, but going to sleep is not the problem, it's this being awakened every day with the "fight or flight" experience. It does indeed make one feel pretty desperate!