http://www.drugfree.org/
1. Some drugs have a sedative effect which slow down the way the body and brain function.
2.Stimulant drugs can produce anxiety or panic attacks particulary if taken in large quantities.
3.Hallucinogenic drugs sometimes produce very disturbing experiences and may lead to erratic or dangerous behaviour by the users.
4.Injection also carries the risk of infection by blood borne diseases if any injecting equipment is shared.
5. Snorting drugs like amphetamine or cocaine powder up the nose on a regular basics can lead to damage to the nasal.