Psycho addiction

Psycho addiction is a form of addiction which can occur in Fallout, Fallout 2, Fallout 3, Fallout: New Vegas and Fallout Tactics.

Fallout, Fallout 2, Fallout Tactics
Using Psycho carries a 20% chance to become addicted. Once addicted, the character suffers a -2 penalty to Intelligence. The addiction lasts for 1 week.
 * In Fallout Tactics, the player can gain the Psychotic Perk which reduces the severity of Psycho Withdrawal.
 * In Fallout this addiction is refereed to as "Psycho Craving" while in Fallout 2 it is refereed to as "Psycho Reliance".

Fallout 3, Fallout New Vegas
Using Psycho carries a 20% chance to become addicted and reduces Endurance and Perception by -1 each.

Chances of addiction are reduced by the Chem Resistant perk in Fallout 3. Addiction can be cleared by doctors or by Fixer (Fallout: New Vegas only).

Known Psycho addicts

 * Paulie Cantelli (Fallout 3)
 * Violet (Fallout: New Vegas)
 * Ricky (Honest Hearts): During Happy Trails Expedition, a Medicine check allows the player to tell Ricky that his 'unwarranted hostility and general agitation' are signs of a Psycho addiction.
 * Mobius (Old World Blues)

Behind the scenes

 * The picture is a reference to several horror movie antagonists. The hockey mask refers to Jason Voorhees from Friday the 13th, the long claws and striped sweater refer to Freddy Krueger from A Nightmare on Elm Street, and the chainsaw is a nod to Leatherface from The Texas Chainsaw Massacre as it says "Made in Texas".