Methamphetamine has a half-life of 12 hours, compared to cocaine which has a 1 hour half-life.
Research has shown that psychosocial factors, antisocial personality disorder and alcohol dependence can play a role in long-term marijuana use.
The effects of fentanyl are felt almost immediately and it is very effective in treating even the worst cases of pain, sometimes referred to as breakthrough pain.
Research has proven that long-term drug use results in changes in the brain that can affect the person long after they have stopped using drugs.