When Percocet users overdose, they will typically feel restless and nauseous and then progress into loss of consciousness and abnormal breathing which may result in death.
Rock or crack cocaine can be easily be smoke, the most common form of use in the streets.
Research indicates that, like cocaine and other abused drugs, opiates activate the brain's reward system causing pain relief, a sense of euphoria and pleasure.
The effects of amphetamines often dissipate within a few hours or days.