In retrospect, i see that i posted off subject. Mea culpa. This is a general question/topic not mrs. D's son.
When substance abuse occurs in my workplace (i'm a state govt. Employee at a university/hospital). The employee is offered counseling/therapy/rehab under their health insurance. Relapses are dealt with under the advisement of their doctor, they still keep their union employment. Everyone is unionized, both staff and physicians, there are specific guidelines.