One out of 10 teenagers said they have used fentanyl patches, a form of narcotic painkiller, a study showed Thursday.

The Ministry of Gender Equality and Family published the results of the biennial survey about harmful environments for youth, which was conducted with the participation of 17,140 students from the fourth grade of elementary school to middle and high schoolers. For the first time this year, questions on the use of narcotic drugs were added, though only for middle and high school students.

Of the total, 10.4 percent of the middle and high school respondents said they had used the fentanyl patch, while 0.9 percent said they had taken Dietamin, an appetite suppressant commonly called "butterfly medicine" due to its shape.

Of those who used fentanyl patches, 94.9 percent said they got prescriptions from a hospital, while 9.6 percent said they purchased the medicine secondhand, implying the possibility of drug trafficking.

Fentanyl is administered to patients with severe pain, such as cancer patients, and it is known for its strong addictive and hallucinogenic effects. The United States particularly has recently been experiencing a fentanyl epidemic, as seen in a recent viral video of people on fentanyl wandering around in a daze, leading to its nickname, the "zombie drug." The Ministry of Food and Drug Safety prohibits fentanyl prescriptions for noncancerous pain of patients under the age of 18, but prescription is allowed with a clear medical purpose.

The survey, however, was not able to distinguish whether fentanyl had been prescribed for medicinal use or was illegally given to addicted teens.

"In the next survey, we will add more detailed questionnaires to figure out the amount of prescribed narcotic painkillers, the purpose of the drugs, and whether adolescents have handed over the drugs to others," Kim Seong-byeok, head of the youth policy division of the Gender Ministry, told The Korea Herald.

Meanwhile, 13.7 percent of middle and high school respondents said they had consumed alcohol, up from 11.6 percent in 2020, while smoking decreased slightly to 4.2 percent from 4.6 percent in 2020.

Nearly 50 percent of all respondents said they had watched restricted videos, up from 37.4 percent in 2020. The category in the survey included not only illegal videos such as pornography, but also R-rated movies and TV series.

Especially, the portion of elementary school students watching restricted videos has increased sharply throughout the years, from 19.6 percent in 2018 to 33.8 percent in 2020 and 40 percent in 2022.