74 I get what you are saying but in my last “group”, we had two who were deathly allergic to two different antibiotics.
Myself and the ‘cillins’, and the other to sulfa drugs.

I keep/kept sulfa drugs on hand, cause they work the best for me. However on a hunting trip where he was injured and the sulfa drug offered, I received a look like I was trying to poison him. A few months later and the opposite happened.

As to shelf life, while many are viable past two years, this is one area where I am ultra conservative, especially when children are concerned. Post-shtf lack of antibiotics may be a killer, but the lack of treatment for an allergic reaction to that antibiotic surely will be.