I have had these same sort of anxiety attacks, they are awful. I do not believe that methadone has anything to do with having them, I was also told this by a doctor. I do know I was given medication for about a 3 month time frame and then taken off, as of this time thay have not returned. If you wish I can find out what this medication was, maybe it would help you. I also got to the point I thought I was losing control. Please get in touch if there is any way I can help. --Chris