Teens are reporting an increased use of synthetic human growth hormone, or HGH. The nationally projectable survey results were released on July 22 by the Partnership for Drug-Free Kids.

The latest Partnership Attitude Tracking Study, PATS, which is sponsored by MetLife Foundation, indicates that 11 percent of teens in grades nine through 12 report “ever having used” the synthetic growth hormone without a prescription. This number is more than double the five percent who responded the same to the question in 2012.

Steve Pasierb, President and CEO of the Partnership for Drug-Free Kids, said in a statement, “These new data point to a troubling development among today’s teens. Young people are seeking out and using performance-enhancing substances like synthetic HGH – and supplements purporting to contain HGH – hoping to improve athletic performance or body appearance without really knowing what substances they are putting into their bodies.”

Pasierb continued, “These are not products that assure safety and efficacy. Prescription and over-the-counter medicines must go through rigorous testing to be proven safe before being sold to the public, but supplement products appear on store shelves without regulation from the Food and Drug Administration and must actually be proven unsafe before being removed from sale.”

According to WebMD, some users turn to HGH in an effort to build muscle and improve athletic performance.