Marijuana smoke also contains more cancer-causing agents than tobacco smoke. Although there is no evidence that marijuana is physically addictive, there is evidence that long-term use is psychologically addictive. Cocaine Cocaine, which can be inhaled through the nose, injected or smoked, stimulates the central nervous system. Its effects include dilated pupils, elevated blood pressure, heart rate, respiratory rate and body temperature. But that's only the beginning.
Chronic use can ulcerate the mucous membrane in the nose.
Crack is one of the most popular and most addictive forms of cocaine. Smoked in a pipe, the effects of crack cocaine can be felt within 10 seconds. Repeated use can lead to addiction within a few days. Continued use can produce violent behavior and psychotic states similar to schizophrenia. Crack also has been linked to sudden deaths from cardiac arrest or respiratory failure.