Kona

Cigarettes are items found in the Consumables menu; you will start the game with five, and can find more while exploring the town. If a cigarette is smoked, Carl's mental health will go back to full, but you'll lose some health in the process.

If you select the cigarettes in your inventory, you can press to discard them entirely and not have to worry about accidentally smoking them (even if you don't, it's a two-part process – you'd need to equip them, then actually press the button to smoke them, so accidentally smoking is hard to do).

If you're worried about mental health (and generally, you shouldn't, as it refills generously at campfires), keep Pain Killers in your inventory and you'll be fine.