I have had problems with nausea for most of my life. It started when I was about 12. I would wake up at approximately the same time nauseous and vomiting. The doctors ran a gauntlet of tests and came up with nothing. This comes and goes over the years. It may last for days, weeks, or months. I have found no connecting factors like diet or sleeping schedule. It occurs even in times of no stress. Has anyone else had this problem or any ideas and solutions doctors missed?

If you are female and 12 when you hit puberty, I would suspect hormones. The same hormones that cause nausea in the menstrual cycle and most specifically pregnancy.
The pill might help even them out.

I really have no idea as to solutions, as you know we can't diagnose here on AMHD, you are a long time member.

Were these just general practitioner doctors? Did you have any referrals to specialists? What are your underlying health issues? What kind of meds are you on?