Administration statistics show that fewer former residents are relapsing within three years of completing their compulsory two years of rehab. The percentage of those not relapsing has risen from 25 percent in 2015 to 33 percent in 2016 and 41 percent last year, one of the highest in China.

Some high-tech approaches, such as virtual reality and artificial intelligence, have also been used in the city's rehab centers to help residents turn their lives around more quickly, the administration said.

A system that allows drug users wearing a special helmet to "walk into" virtual hotel rooms and karaoke bars and watch people take drugs provides them with a more effective desensitization treatment than the traditional use of pictures of narcotics, Wang said.