The plant that produces marijuana is the hemp plant cannabis sativa. The pharmacologically active ingredient in marijuana is tetra-hydro-cannabinol (THC).
Marijuana is used to heighten perception, affect mood and relax. It is estimated that about 30 percent of adults in the U.S. use marijuana.
Many people think marijuana is harmless. This assumption is wrong. Signs of marijuana use include red eyes, lethargy and uncoordinated...
