I've been taking your advice for my adrenal fatigue for just about a year now (anniversary this month!) and it's been quite a journey. The past few weeks, my insomnia has been almost completely gone and I've been doing very well.
I have been taking triphala powder (1/2 teaspoon before bed) on and off, but decided to up it to 1 tsp as I seemed to be tolerating it well; also three nights ago I started doing this every night. I didn't have constipation or anything but just liked the type of regularity that it gave me, and made me feel like I wasn't "holding anything in"!

Two nights ago though my sleep got slightly spotty again and in my experience this can be insomnia "creeping" back in. Wondering what might have caused it (although there was a bit of stress about a week ago which could be having a delayed effect), I quickly did some internet searches to see if triphala had any relation. Of course it's taken to cure many things, at a low dose they say it's good for everybody and I've certainly used it before, just never on a daily basis for general well-being. I saw somewhere that due to its "warming" properties (ayurvedic terminology) it can cause insomnia. Wonder what your thoughts are? I will probably abstain for a couple of days to see what happens.

Triphala is not really a central nervous system stimulant so it should not cause insomnia.  It does boost the adrenals though, which could lead to an increase of epinephrine that can cause insomnia.  Epinephrine is kicked out in cases of allergic response, stress and low blood pressure.