Adrenaline

Adrenaline Pills are items scattered around Liberty City in Grand Theft Auto III and Vice City in GTA Vice City that when collected by a person give a temporary boost of speed while seeming to slow down time. While the game's speed is slowed down, the player's aiming speed is the same as it would normally be, which is handy when engaged in gun battles such as police, gangs or during rampages. You can also jump further than normal. Strangely, entering a vehicle resets the speed to normal again.

In Grand Theft Auto San Andreas,the "Adrenaline Effect" is used as a cheat code.It still has the same affect.