Concerns over the side effects of acetaminophen products, including Tylenol Extended Release (ER), have been growing in Korea following the European Commission (EC) suspending their marketing licenses.
The Ministry of Food and Drug Safety (MFDS) Tuesday said it is considering whether to stop marketing authorization of the drug, distributing safety letters on the risk of acetaminophen overdose following the EC's decision.
The European Commission last month suspended the marketing authorization of products that have “paracetamol, modified and prolonged release” in the framework of Article 31, causing the Korean health authorities and a pharmacy group to raise further safety concerns on the use of Tylenol in the country.
Acetaminophen or paracetamol has been found to cause liver damage when taken in large doses. In Korea, 18 companies sell prolonged-release acetaminophen drugs including Janssen Korea’s Tylenol ER. A total of 24 companies sell 45 types of acetaminophen-containing prolonged release formulations, which also includes Janssen’s Ultracet ER.
The ministry said it would take an active role in informing doctors, pharmacists, and other professional organizations regarding the prescription, manufacturing, and sales of the drug while gathering data on drug use abroad and in Korea to come up with future measures.
Acetaminophen is still used in the U.S. and Canada, the ministry noted, saying that the benefits outweigh the risks if taken at an appropriate dose. The MFDS recommends 2 tablets of 650 mg and four tablets of 325 mg of paracetamol in modified and prolonged release form every eight hours for those over the age of 12.
People should not take more than six pills of 650 mg or 12 pills of 325 mg of extended release in a 24-hour period. Adults should take one pill of mixed paracetamol products with 12-hour periods in between taking the drug and not exceed four pills a day.
The drug also should not be taken with other acetaminophen-containing ingredients since exceeding the maximum daily dose of 4,000 mg may cause liver damage.
On Wednesday, the Korean Pharmaceutical for Democratic Society called on the MFDS to withdraw the drugs from the country, saying that a large-scale side-effect study should be performed to lower the once daily dosage rate.
"The controversy over the hepatotoxicity of acetaminophen has been going on for years," the organization said. "It was not only the biggest cause of hepatic insufficiency in the United States, but there have also been reports showing it could lead to liver transplantation and death."
The group criticized the ministry for taking no other action than issuing a letter on drug safety despite multiple calls for follow-up measures in 2011. The organization noted that the U.S. FDA opened a public advisory committee in 2009 to discuss the side effects of acetaminophen on liver toxicity and requested limiting prescriptions to 325 mg in 2011.
Amid the growing concerns, a Janssen Korea official noted that the ministry report notes that the drug has therapeutic effects if taken at the proper dosage amount.
“Fundamentally, Janssen Korea thinks of the patient’s safety. As the MFDS report notes, the drug can treat patients if he or she complies with the recommended drug concentration amount,” the Janssen Korea official said.
The extended-relief version of Tylenol leads the Korean painkiller market, having recorded around 27 billion won ($25.3 million) in sales, according to IMS data.