Accumulating medications may be simple when it comes to finding aspirin and other non-prescription drugs but prescription drugs will be hard to get for those who can’t write their own prescriptions or don’t have a relationship with an understanding physician who can.
Antibiotics are a case in point. I consider this a major issue because there will be a much larger incidence of infections when people have to fend for themselves, and injure themselves as a result. Simple cuts and
scratches from chopping wood can begin to show infection, in the form of redness, heat and swelling, within a relatively short time. Treatment of infections at an early stage improves the chance that they will heal quickly and completely. However, many preppers, being the rugged type, are most likely to ignore the problem until it get much worse and spreads to their entire body, causing problems that could eventually be fatal. Having antibiotics readily available would allow them to deal with the issue until medical help (if available at all) arrives.