The leaves of the plant kratom.
The herb kratom has a large following and is so popular that it is sold in vending machines. The FDA recently issued a public warning about the herb, which contains low levels of opioids.
Cannabis is on display at Shango Premium Cannabis, in Portland, Oregon, Sept. 30, 2015.
Timothy J. Gonzalez/AP
The trend toward marijuana legalization is growing, but the legality, or illegality, of cannabis at the federal level hasn't changed at all.
A new leaf.
Bolivia is the first cocaine-producing country to take a harm reduction approach to tackling the drug trade.
Potential medicine, or dangerous drug?
Complaints about the ban of kratom, often used by recovering opiate addicts, have been vociferous, but not always backed by facts.
Mr High Sky/Shutterstock
147m people used the drug last year. We need to know much more about it.