No doubt that it's mood altering.  But so is alcohol, prescription drugs, OTC drugs, general food, & sugar.  All those things start mood changes in people. Sugar makes kids very rambunctious and now overly diagnosed as ADHD or ADD.

But you should have the right to do what u want.  And it's unfortunate that she seen that in him ... but as soon as he started . she should've left him.  I'm sorry she experienced such situations ... but some men get violent without help from any meds or alcohol.  Sometimes mere frustration gets them.  And if it wasn't' the steroids then I'm sure something would've made him strike out.