Drugs transmitted through breast milk

Here is the article:

https://patch.com/pennsylvania/wilkes-barre/s/ggw2v/bucks-co-mom-killed-infant-son-with-tainted-breast-milk-da

So an addicted mom who takes amphetamines and methodone is branded a killer. Who prescribed the methodone and told her to go ahead and breast feed? Was she not told? Wouldn’t the prescriber be indicted instead?

What about moms addicted to antidepressants, prescribed drugs like Ritalin and more who have babies? Are they killers, or are their doctors killers?

If she was told to take the methodone then this sounds prescribed. It was the prescriber’s responsibility to tell her, no?

Feedback and comments welcome!