Needle exchange programs, like this one in Portland, Maine, offer free, sterile syringes and needles to drug users. The programs save money and lives, health officials say, by curtailing the spread of bloodborne infections, such as hepatitis and HIV. Robert F. Bukaty/AP hide caption

itoggle caption Robert F. Bukaty/AP

Workplace drug testing for marijuana may need updating in light of changing laws, a case before the Colorado Supreme Court suggests. Kai-Huei Yau/MCT/Landov hide caption

itoggle caption Kai-Huei Yau/MCT/Landov

A man smokes marijuana outside Uruguay's parliament in Montevideo on Wednesday, where lawmakers in the lower house debated and passed a bill that would legalize marijuana and regulate its production and distribution. Matilde Campodonico/AP hide caption

itoggle caption Matilde Campodonico/AP

The United States Supreme Court: a temple to complexity and self-reinforcing feedback loops? Chip Somodevilla/Getty Images hide caption

itoggle caption Chip Somodevilla/Getty Images

The number of new drug shortages each year in the U.S., from 2001 through Dec. 21, 2012. University of Utah hide caption

itoggle caption University of Utah