In Undead Nightmare, you'll be dealing with the undead, not illnesses, and you'll need to find other resources to stay alive, like:
* Anti-Zombie Tonics: These can be found in various locations, including abandoned houses and barns.
* Fire Bottles: These can be crafted from Molotov Cocktails and are essential for dealing with hordes of zombies.
* Bullets: These are crucial for defeating tougher enemies and are available at gunsmiths and scattered around the world.
Remember, the focus in Undead Nightmare is on survival against the undead, so your primary concerns will be finding weapons and resources to keep yourself alive.