I think the answers of a deficiency or thyroid sounds very likely. Yes, I think your doctor would have checked that right away. Mine cheeked that, first thing.

Yes..but mine is thyroid related. But...it is also autoimmune...many of these disorders go hand in hand.

I have also been on Norco for 18 years...I believe mine has been 100% thyroid related. I have Hashimoto's Thyroiditis...very common to have it along with fibro. They frequently go hand in hand.

It happened to my husband who does not have fibro. He started taking good vitamins and other supplements and it looks like they are getting fuller. Maybe some defficiency?

You never know why all of a sudden your hair just starts falling out. Mine did that same thing. I had been on the medication for a couple of years and then all of a sudden my hair and eyebrows started falling out. It may not be your reason, just a suggestion. I was on a harsh medication for arthritis, so I had to go off it.