A Bulgarian border policeman stands near a barbed wire wall on the border with Turkey in July 2014. Experts believe that about two-thirds of the heroin that enters Europe comes through Bulgaria, and that a third of that moves on to the United States. Dimitar Dilkoff/AFP/Getty Images hide caption

itoggle caption Dimitar Dilkoff/AFP/Getty Images

Sabas Sanchez Jr. was better known among his neighbors in Madison, Neb., as "Gordo" — Spanish for chubby. He also had an oversized personality. His father keeps this tattered photo in his wallet. Bobby Caina Calvan/Heartland Reporting Project hide caption

itoggle caption Bobby Caina Calvan/Heartland Reporting Project

Stacy Emminger holds the death certificate for her son, Anthony, who was addicted to heroin. His death was marked as a multidrug toxicity in Pennsylvania. Ben Allen/WITF hide caption

itoggle caption Ben Allen/WITF

Shannon Rivers, a member of the Akimel O'odham tribe, lights a fire for the purification ceremony at the Coconino County jail. Inmates will help him put blankets over the sweat lodge structure, place heated rocks inside and pour water over them. Laurel Morales/KJZZ hide caption

itoggle caption Laurel Morales/KJZZ

Families harvest poppy bulbs in the Badakhshan province of Afghanistan. To collect the opium, they score the bulbs and let the milky substance ooze out. The dried residue contains about 10 percent morphine. David Guttenfelder/AP/National Geographic hide caption

itoggle caption David Guttenfelder/AP/National Geographic

Volunteer Patrick Pezzati searches yards in Turners Falls, Mass., for discarded heroin needles. Karen Brown/WFCR hide caption

itoggle caption Karen Brown/WFCR

Volunteers search for needles and other drug paraphernalia along Church Street in Austin, Ind., in April. The region has recorded 142 new HIV cases since December, according to the state, in an outbreak tied to injected-opioid use. Seth Herald/Nurphoto/Corbis hide caption

itoggle caption Seth Herald/Nurphoto/Corbis
Frederica Boswell/NPR

In Philadelphia, some drug users are selling clean needles from needle exchange programs on the street. Researchers say the black market isn't necessarily a bad thing. ImageZoo/Corbis hide caption

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Tina Wolf demonstrates the use of naloxone to community members in Lindenhurst, N.Y., during an overdose prevention training. Georgia Dolan-Reilly (left) of the Suffolk County Prevention Resource Center helped with the training. Kevin Hagen for NPR hide caption

itoggle caption Kevin Hagen for NPR

Several states distribute Naloxone hydrochloride, also called Narcan, to treat opium-based drug overdoses. But only one company manufactures the drug, and the price has spiked in recent years. Toby Talbot/AP hide caption

itoggle caption Toby Talbot/AP

Soldiers in the Afghan National Army's 6th Kandak (battalion), 3rd company, search a local farmer's poppy field during a joint patrol with U.S. forces in Kandahar province in March of last year. Andrew Burton/Getty Images hide caption

itoggle caption Andrew Burton/Getty Images