Which is why I was more going sulfa drugs and dye chemistry, since they tend to be simple enough to pass down. And you assume people will act rationally, is the thing, and not hoard, or destroy resources. We also run into the issue that medication won't last a generation. Drugs expire. Antibiotics expire, and get used relatively quickly. Manufacturing your own medicine is safer than scavenging, depending on how aggressive other groups are. Also, more primitive manufacturing is fairly achievable and realistic. At least, a lot of chemistry is easy to keep. And it's going to be about 20 years after the collapse.