after reading up on this herb/plant.
it seams that humans should not take while pregnant but ok for after to help milk.
also it would seem when it comes to diabetes one should be careful since there is more than one type of this condition.
as for toxic I only found this:
Goat’s rue is toxic to ruminates, especially sheep. Livestock and wildlife losses could be expected to increase especially during dry years if animals graze in infested areas.
I would think it could be toxic to humans as well if taken in to large of doses. or for to long. hence the 6 weeks on and 6 weeks off.