Medical marijuana is legal in 23 states, the District of Columbia and Guam, and recreational use of the drug is legal in Washington State and Colorado.
Marijuana’s medicinal uses can be traced back as early as 2737 B.C., when the emperor of China, Shen Neng, touted cannabis tea as a treatment for gout, rheumatism, malaria and even poor memory, writes Mitch Earleywine, a professor of psychology at the State University of New York at Albany who researches drugs and addiction, in “Understanding Marijuana: A New Look at the Scientific Evidence” (Oxford University Press, 2005). The drug’s popularity as a medicine spread throughout Asia, the Middle East and then to Africa and India, where Hindu sects used it for pain and stress relief.
in the united state pain is the most common desease in which peoples take medical cannabis, science shows that the drug is effective in neuropathic pain.
But now most of the people are taking weed as their need and habit, if u take this as a medical purpose then its good otherwise it can be harmfull for you.