“Having the Chem Resistant perk means you're 50% less likely to develop an addiction to chems, like Psycho or Jet.”— Fallout: New Vegas in game description
Having the Chem Resistant perk reduces the chance to develop an addiction to chems, like Psycho or Jet, by 50%. This perk is rendered useless if the Courier opts for Logan's Loopholetrait in Old World Blues. When stacking Chem Resistant with the Old World Gourmet and Brainless perks, it results in a 72% resistance to addiction.
Fallout 4
“All the rush without the hassle! Can't get enough of Jet, Psycho, or Buffout (or any other chem, including the ones you've made yourself at a chemistry station)? Then lessen (and finally remove) the downside of chem addiction completely. This is essential if you plan on enhancing you routines with chems.”— Fallout 4 Vault Dweller's Survival Guide description
Chem Resistant is added to the game with the Fallout: New California expansion. Whenever a player character is about to become addicted by taking a drug, they can instead chose to take 3 damage instead. They can also chose to discard the perk card in order to lose the Addicted trait.
, Brainless and Day Tripper perks.
