Doctors in South Korea went ahead with prescriptions for GLP-1 weight-loss drugs such as Wegovy and Mounjaro more than 70,000 times over roughly two years even after a system flagged that the patient was already taking the same ingredient, data showed. Because the safeguard against duplicate prescribing stops at a warning on the screen, the number of such cases is climbing faster this year.
Rep. Seo Young-suk of the Democratic Party of Korea, a member of the National Assembly's Health and Welfare Committee representing Bucheon-A, released the data on the 21st after obtaining it from the Health Insurance Review and Assessment Service. According to the data, prescriptions were maintained even after a same-ingredient duplication alert in 70,018 cases from October 2024 through August 2026. The alert appears on the screen where a doctor enters a prescription, but there is no way to stop the prescription once the doctor sees the warning and does not change it.
The Drug Utilization Review (DUR) system notifies doctors on the prescribing screen when a patient has received a drug with the same ingredient from another medical institution and the dosing periods overlap. It has no function that forces a prescription to be changed after the warning is seen. In practice, it amounts to a notification and nothing more.
The number of prescriptions maintained after an alert was 31,164 in 2025. Through August of this year, the figure reached 38,466, or 23.4% more than the full-year total for last year. The number of patients involved also rose, from 24,742 in 2025 to 31,597 in the first eight months of this year.
By drug, cases involving semaglutide, the main ingredient in Wegovy, totaled 27,420 in 2025 and 15,101 through August of this year. Cases involving tirzepatide, the main ingredient in Mounjaro, which launched in South Korea in August 2025, jumped to 23,321 in the first eight months of this year from 3,332 in 2025.
The bigger problem is that no alert appears at all when a patient is prescribed weight-loss drugs with different ingredients, such as Wegovy and Mounjaro, at the same time. The DUR system checks for duplication of the same ingredient, but weight-loss drugs are left out of the therapeutic-class duplication check that looks at whether drugs with similar effects are being used together. If a Wegovy patient obtains Mounjaro from another hospital, the system shows nothing.
There are also no statistics on how often this form of duplicate prescribing occurs. Seo's office requested data distinguishing whether patients with duplicate prescriptions had used two hospitals or three or more, but the review service replied that such a figure would be difficult to produce.
Seo argued that the system should be strengthened by adding weight-loss drugs to the DUR therapeutic-class duplication check and by requiring doctors to record their reasons when they maintain a prescription despite a same-ingredient alert. The lawmaker also noted that repeated prescriptions from multiple hospitals with overlapping dosing periods could lead to drug misuse and illegal secondhand trading.
On June 5, 2026, the Ministry of Food and Drug Safety gave advance administrative notice of a revision that would additionally designate preparations containing liraglutide, semaglutide and tirzepatide as drugs at risk of misuse. At a parliamentary audit of government agencies on Oct. 13, 2026, Minister Oh Yu-kyoung said the measure was under regulatory review by the Office for Government Policy Coordination but did not say when the final notice would be issued.
The scale of prescribing is also growing quickly. The number of Wegovy prescriptions screened through DUR totaled 395,379 from its launch on Oct. 15, 2024 through June 2025. For Mounjaro, a cumulative 1,501,161 prescriptions were screened through DUR within 10 months of its launch.