I didn't know what was going on. I got this sharp stabbing pain in my upper back. I started to realize it was timed. Lying in bed with the pain, I counted the seconds. The stabbing pain started, lasted for exactly 10 seconds, stopped for 45 seconds. Started again for the same seconds!
This went on for about two hours! I don't remember the rest, I must have fallen asleep. The next morning I got a few twinges of the pain, then nothing after that. What in the heck was that? I am on 100mg of atenolol and have been for some time with no problems. This was the strangest thing I have ever encounted, has anyone else felt this?