Not sure if it'll do anything for you but it surely is safe. My SO is taking 20mg per day for years (for glioma, not insomnia, it's way too high dose to work for insomnia). She had a break from it for few months during which her tumors started regrowing, might be coincidence.

Tolerance, vivid dreams, and anxiety in some.

It seems like a free lunch because we are starving ourselves for it. We need a lot more than we produce endogenously under artificial night lighting.