The situation of a person overdosing time after time is perhaps due to the fact that these aren't over the counter products being consumed. Too obvious?
Accidental overdoses occur due to unknown strength or purity of dosages, and unsupervised use. Nobody has died using a safe injection site. Too obvious?
If brains were candidates for organ harvesting yours wouldn't be at the top of the pile. Not if wanting a compassionate society was considered valuable.