Phentermine and other psychotropic drugs prescribed as ‘diet pills’

Psychotropic drugs, including phentermine, which is often referred to as a “butterfly drug” and is used to suppress appetite by stimulating the central nervous system, are being prescribed under the guise of diet pills, a report said.

Rep. Lee Ju-young of the Reform Party said Monday that an analysis of the yearly data of psychotropic drugs prescribed as diet pills in the last five years at the Ministry of Food and Drug Safety showed that more than 1,079.29 million psychotropic drugs were prescribed to over 8.35 million patients as diet pills from 2020 to June this year.

By ingredient, Dietamin Tab, which contains phentermine as the main ingredient, and Phendira Tab, which contains phendimetrazine as the main ingredient, were prescribed to 7,208,159 patients from 2020 to June this year. Phendira and Dietamin tablets accounted for 86.3 percent of all prescriptions in terms of patients and 92 percent of the total number of prescriptions.

Notably, about 402,000 pills of lorcaserin-based psychotropic drugs, which were approved in Korea in 2015 as psychotropic appetite suppressants, were prescribed to 7,109 patients in 2020, 2021, and 2022, despite the U.S. Food and Drug Administration's (FDA) decision to stop prescribing and recall them in February 2020 following a warning of an increased risk of cancer.

“Diet pills with ingredients, such as phentermine and phendimetrazine, are medical narcotics that have been recognized to have serious physical harms when misused and abused,” Rep. Lee said. “Patients should be extremely cautious about using diet pills and only use them as a short-term adjunctive therapy after consulting with medical professionals.”