Psycho

Psycho, colloquially termed "angry juice" and "the big red one", is a military-grade, performance-enhancing drug in all Fallout games.

Background
A military-grade psychosis-inducing amphetamine, Psycho is provided in a unique delivery system that mixes strange chemicals of military origin immediately prior to injection. The drug saw its inception in the laboratories of a research division operating under the authority of General Constantine Chase, who used methamphetamine as basis, making the result drug almost like, but legally distinct from it. It entered combat use during the final stages of the Anchorage Reclamation, to reduce the impact of attrition on U.S. forces deployed to the Alaskan front. Its deployment was authorized by General and his chief medical officer, Dr. Adrienn Adami, despite the clinical trials being incomplete at the time.

Its primary effect is an increase in damage resistance and dampening of higher brain functions, intended to create tough shock troops for human-wave assaults. The caveat is that the dampening effect also makes the soldiers hard to control. Some variants of Psycho, based around similar chemicals, also increase combat performance by speeding up reflexes and bodily functions to allow the soldiers to deal more damage, though said variant precluded the damage resistance boost. Both cause them to be particularly jumpy and aggressive.

Due to the rushed nature of the drug development and deployment, numerous side effects manifest as a result of Psycho usage. Chief among these is that the stimulant can cause users with weak hearts to suffer a fatal heart attack. Long term effects include dementia, psychosis, elevated levels of aggression, and general agitation. Addiction aggravates the adverse symptoms. 

Psycho


Depending on the game, Psycho will give different effects. In Fallout and Fallout 2, Psycho increases damage resistance, allowing users to survive more hits in combat. In Fallout 3 and Fallout: New Vegas, Psycho increases the damage dealt. In the latter game, Psycho is an ingredient for the Slasher drug. In Fallout 4, Psycho acts like Slasher did in Fallout: New Vegas, boosting damage resistance as well as the Sole Survivor's damage output.

Slasher


Slasher is a chem which combines the effects of Med-X and Psycho into a single consumable. It is possible to combine the effects of Slasher with Med-X to gain a 50% total boost to damage resistance. It does not stack with Psycho.

Psychojet


Psychojet, like Slasher, combines two chems, Psycho and jet. Psychojet increases damage resistance and slows time for ten seconds.

Psychobuff


Psychobuff is a combination of Psycho and Buffout which gives increases to Endurance, Strength, maximum health, and damage dealt.

Psychotats


Psychotats is a combination of Psycho and Mentats which gives an increase to Perception, as well as damage resistance.