Fallout, Fallout 2, Fallout Tactics
Psycho has a 20% chance to cause an addiction. It lasts for a week. When addicted, the player character suffers a 2 point penalty to Intelligence.
Fallout 3, Fallout: New Vegas
Fallout 4, Fallout 76
Psycho, Psychobuff and Psychojet have a 25%, 35% and 35% chance respectively to cause an addiction. When addicted, the player character suffers a 1 point penalty to Strength and 10 to Damage Resistance. The addiction can be cured by visiting a doctor, taking addictol, eating a radscorpion egg omelette or drinking a refreshing beverage.
- In Fallout Tactics, mutants can gain the Psychotic perk which makes them suffer less withdrawal from Psycho.
- In Fallout 3 and Fallout 4, the Chem Resistant perk can be gotten which makes one less likely to become addicted to chems, including Psycho, and thus less likely to suffer from withdrawals.
- In Fallout: New Vegas, Fixer can be used to remove the Psycho addiction.
- In the Fallout: New Vegas add-on Honest Hearts, during the quest Happy Trails Expedition, a Medicine check allows the Courier to tell Ricky that his 'unwarranted hostility and general agitation' are signs of Psycho addiction.
Behind the scenes
The picture is a reference to several horror movies. The hockey mask refers to Friday the 13th, the long claws refer to A Nightmare on Elm Street and the chainsaw is a nod to The Texas Chainsaw Massacre as it says "Made in Texas."