Amp is a V-World drug. Emmanuelle says it is a hack that bypasses the holoband safeties, interacting with the visual cortex to heighten a player's senses and reflexes. It is dropped into one's eyes like eye drops.
Amp junkies are called ampheads.
Examples
Joseph Adama becomes addicted to amp while searching for his daughter, Tamara, in New Cap City. ("Ghosts in the Machine") ("End of Line")
Amphead is an amp junkie who takes possession of Joseph Adama's flat in New Cap City. ("There Is Another Sky")
Notes
Amp may be short for amphetamine.