I'm working on a mod currently that followers, and I was wondering if it would be worth it to give them drugs like med-x and buffout. Would they use these or do NPCs only use items that restore health like stimpacks(like they do in Oblivion)?

In which case, could I add say a restore 1 health effect to these certain items(copied and renamed) with the condition that the owner is not the player and then expect NPCs to use them in combat?

They only use stimpaks as far as I can tell.
In my Wendy Gilbert mod, you can give her several drugs. I simulate their effects and timing in a script, because actor effects will just 'go away' from NPCs when you go through portals, for example.