In my opinion, possession should be legalized in every case; it's not the government's business what I choose to put into my own body. In the case of dangerous drugs and medications it should be distribution / intent to distribute that's regulated.
Speaking of anti-biotics: we really need clear easy to understand information for places that allow antibiotics over the counter, sometimes in single doses not full courses. This would tell people aboutthe harm they are doing to themselves and to the rest of society.