South Korea says no causal link confirmed in reported Mounjaro pancreatitis cases

South Korea's drug regulator said it has not confirmed a causal link between tirzepatide, sold as Mounjaro, and reported cases of acute pancreatitis in people who took the drug, and that it will continue monitoring domestic reports and overseas safety decisions ^[1].

The Ministry of Food and Drug Safety (MFDS) said three pancreatitis cases tied to tirzepatide products and four tied to semaglutide products had been reported in Korea through March, counting from each product's market launch ^[1]. An MFDS official told reporters that the reports were not filed for reasons of hospitalization, life-threatening conditions, death, serious disability or functional impairment, and that "a causal relationship between the adverse events and the drugs has not been established" ^[1].

The statement followed an online post earlier this month titled "I almost died from pancreatitis caused by Mounjaro," whose author said inflammatory markers and liver enzyme levels rose sharply after a single 2.5 milligram dose of Mounjaro, prompting an emergency room visit ^[1]. The ministry did not say whether it had verified that account.

Pancreatitis and gallbladder disease are already reflected in Korean prescribing information for tirzepatide and semaglutide products, the MFDS said ^[1]. Mounjaro's prescribing information advises caution in patients with a history of pancreatitis; in clinical trials, acute pancreatitis and cholelithiasis were reported as "uncommon," occurring in at least 0.1 percent but fewer than 1 percent of patients ^[1]. Wegovy's label says acute pancreatitis has been observed with GLP-1 receptor agonists and advises patients to be alert for related symptoms, while Ozempic advises caution in patients with a history of acute pancreatitis ^[1].

Regulators elsewhere have acted on the same drug class. The U.K.'s Medicines and Healthcare products Regulatory Agency strengthened its warnings in January 2026 after reports of necrotizing and fatal acute pancreatitis involving GLP-1 and GIP/GLP-1 drugs ^[1]. The European Medicines Agency evaluated the association between semaglutide and non-arteritic anterior ischemic optic neuropathy (NAION) and added the condition to product information as a very rare adverse reaction ^[1].

Why it matters for patients

Reported cases and confirmed causes are different things. The Korean agency's statement means that a handful of pancreatitis reports among people taking tirzepatide and semaglutide did not, on review, establish that the drugs caused the events ^[1]. It does not mean the risk is zero: pancreatitis remains listed as a possible reaction for both ingredients in Korea, and Mounjaro's trial data put acute pancreatitis and gallstones in the uncommon range of 0.1 percent to less than 1 percent of patients ^[1].

The counts also reflect reporting volume rather than a measured rate. Seven reports across two drug classes in Korea, filed over a period of years since launch, do not by themselves show how often the reaction occurs ^[1]. How many of the reports involved confirmed diagnoses, and what other risk factors the patients had, has not been disclosed ^[1].

The drugs in question are the same active ingredients sold in the United States under several brands, including Mounjaro and Zepbound (tirzepatide) and Ozempic, Wegovy and Rybelsus (semaglutide) ^[1].

What happens next

The MFDS said it discussed overseas labeling changes for semaglutide products sold in Korea, including Wegovy and Ozempic, after the EMA's NAION assessment, and that the process of revising Korean prescribing information is underway ^[1]. The ministry said it will keep monitoring overseas safety information and domestic adverse event reports and will consider measures, including label revisions, if new information emerges ^[1].

Separately, the MFDS issued an administrative notice in June proposing to designate tirzepatide and semaglutide as drugs with potential for misuse or abuse ^[1]. If the ingredients are formally designated, warning statements would be required on packaging, and the products would not be available without a doctor's prescription even in areas exempt from Korea's prescription-dispensing separation system ^[1]. Whether that designation has been finalized has not been reported.