Jet Addiction

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

Fallout 2, Fallout Tactics
"Everything is moving so slowly... you need to get some more Jet, right NOW!''"

Using Jet carries a 50% chance to become addicted.

Fallout 3
Using Jet carries a 20% chance to become addicted.