I've had patchy AA since I was about 5 years old. I'm 30 now. Severity has varied over the years (i.e., minimal patchiness in college, really patchy in 2015, but never total scalp loss at any point in my life). I started on Xeljanz towards the end of 2015 and still on it today (3 per day for last 13 months). Hair looks much better than it did when I started the medication but I still have a few stubborn spots in my front hairline.
Eyebrows and lashes started noticeably thinning in 2015.
To answer your question, I think if I stopped taking X then things would get worse. There's currently a lot of research being done on using JAK inhibitors to treat AA so hopefully in the not too distant future there are more targeted treatments with better safety profiles.
Hey! I have had alopecia for one year now. I only have 2 spots one on the top of my head and one by my ear. Both are like an inch big? My mom had alopecia in her 20's two spots as well and they both grew back and never returned. Hoping mine goes the same way. Both of my patches are starting to grow back, crossing my fingers that they keep growing! My patch that I discovered first has long hairs like 2 inches long in some places but the one by my hear is more recent so only has little hairs and some parts with no hair.
I have patchy alopecia currently, one on the back of my head- hair is growing in in some spots but not in others. I had two spots originally, but the other spot went away. I guess that the key thing to get is that for most people the spots will fill in. Don't worry about it, the more you worry, the more stress you get (which can be a cause of AA.) I've had my AA since August and i've had a few bald patches on my legs, but no thinning on my eyebrows or eyelashes. The odds are is that you'll be fine, so don't worry about it too much!