Diethylene glycol in medicines, from 1937 to the WHO alerts

On November 18, 2008, Nigeria's Federal Ministry of Health received a report of 13 children with unexplained kidney failure at one hospital in Lagos state. Three days later, the national drug regulator found diethylene glycol in four batches of an acetaminophen teething syrup. By the end of the investigation, 57 children aged 3 or younger had been poisoned and 54 had died, CDC reported in 2009¹. Six bottles collected from patients' homes contained 17 to 21 percent diethylene glycol by weight.

CDC counted at least 12 such mass poisonings over the previous 70 years, with at least 450 deaths. "In all but one of the 12 DEG mass-poisoning events," the report said, "propylene glycol or glycerin was the intended diluent."

That pattern has held since. Diethylene glycol (DEG) and its chemical cousin ethylene glycol (EG) are industrial solvents and antifreeze agents that "should never be found in medicines," the World Health Organization says⁵. Both keep turning up in cough and fever syrups, usually because glycerin or propylene glycol was contaminated or substituted somewhere upstream. This history runs from the first US disaster in 1937 through the 2022 to 2025 alerts issued by the World Health Organization, and ends with the testing rules FDA restated in 2023.

From 1937 to Haiti

Its earliest entry in FDA's account³ is American. In 1937, a liquid sulfanilamide that used DEG as its solvent killed 107 people, many of them children, a disaster told in our case history of the Elixir Sulfanilamide deaths. It led to the 1938 Food, Drug, and Cosmetic Act and its requirement that drugs be shown safe before sale.

Later cases came mostly from overseas, and in a different form. The solvent was no longer chosen on purpose. It arrived as a contaminant in glycerin or propylene glycol, two common excipients, the inactive ingredients in a medicine. Between 1990 and 1998, DEG poisonings in Argentina, Bangladesh, India and Nigeria killed hundreds of children, according to FDA's 2023 guidance³, which cites a 1997 WHO workshop report.

Haiti's outbreak is the best documented of that decade. From November 1995 through June 1996, acute kidney failure was diagnosed in 86 children aged 3 months to 13 years, most of them 5 or younger. Ten were transferred to US hospitals for intensive care and dialysis, and nine survived. Of the 76 who stayed in Haiti, only one was known to have survived, CDC reported². Investigators traced the illness to two locally made acetaminophen syrups whose glycerin had been imported contaminated with DEG.

That CDC report also made a technical point that would come up again. The infrared spectroscopy identity test then required by the United States Pharmacopeia "would not have detected this DEG-contaminated glycerin," it said. A gas chromatography method could. It also noted a cluster of 14 deaths in one hospital in India among patients given contaminated glycerin.

In October 2006, DEG poisoning struck Panama, causing illness and deaths, FDA's guidance says. Then came Nigeria in 2008. Its investigators found the same failures seen before, according to the CDC report¹. The maker used unknown or unapproved suppliers for propylene glycol, had no certificates of analysis, did no identity testing on the propylene glycol, did not analyze finished product for DEG, and did not track where its product went. About 28 percent of the poisoned children were given the syrup after the recall was announced.

The 2022 to 2025 alerts

In September 2022, The Gambia reported four contaminated syrups to WHO. Laboratory analysis "confirms that they contain unacceptable amounts of diethylene glycol and ethylene glycol as contaminants," the WHO alert of October 5, 2022⁶ said. By January 2023, contaminated syrups had been reported from at least seven countries, associated with "more than 300 fatalities in three of these countries," most of them children under 5, WHO said in a January 23, 2023, statement⁵. The alerts kept coming.

For each contaminant, the accepted limit is no more than 0.10 percent, as WHO's Iraq alert¹¹ noted. The Cameroon syrup, by WHO's July 2023 alert¹⁰, held 286 times that much DEG. The Indonesia⁷, Uzbekistan⁸ and Pacific islands⁹ alerts followed the same template, listing products and batches and asking regulators to pull them.

Pakistan's alerts moved the problem up the supply chain. In April 2024, WHO reported falsified propylene glycol¹² labeled as pharmacopeial grade, with EG contamination as high as 100 percent, meaning the tested sample was entirely ethylene glycol. The most recent alert, on October 13, 2025¹³, followed what WHO called "localized clusters of acute illness and child fatalities in India." Indian regulators told WHO none of the products had been exported.

What FDA's 2023 guidance requires

In May 2023, FDA reissued its guidance on testing high-risk components, effective immediately. The guidance page⁴ names five ingredients in its title: glycerin, propylene glycol, maltitol solution, hydrogenated starch hydrolysate and sorbitol solution. Its footnotes add others whose USP-NF monographs include DEG and EG tests, such as polyethylene glycol and noncrystallizing sorbitol solution. At the time, FDA said, it had "no indication that any contaminated products connected to the recent international incidents have entered the U.S. drug supply chain."

Much of the guidance restates existing law. Under FDA's good manufacturing practice rules, at least one test must verify the identity of each component, and "specific identity tests, if they exist, shall be used," according to 21 CFR 211.84¹⁴. Representative samples of each shipment of each lot must be tested before use. Where a USP-NF monograph includes the DEG and EG limit test, a manufacturer must run it and find no more than 0.10 percent before using the ingredient, the guidance³ says. It adds that the infrared part of the USP glycerin identity test "is not suitable for detection or quantitation of DEG or EG," the same gap CDC flagged in Haiti.

FDA's new recommendations go further. Because FDA has seen "wide variability of DEG and EG contamination from container to container," it recommends testing a sample from every container in each lot. Drug makers should know the original manufacturer of each high-risk ingredient and every repacker or distributor in between. Repackers and distributors should test what they sell for drug use, and compounders should test each lot or confirm that a reliable supplier did. The guidance's background lists what the earlier outbreaks had in common. Makers relied on a certificate of analysis, the certificate was often a copy on a distributor's letterhead, and the ingredient's chain of custody was unknown. Our piece on excipients and their supply chain covers how those ingredients move.

What US recall records show

None of the 18,076 drug recall records in openFDA's enforcement data¹⁵ from 2012 through October 28, 2026, mention diethylene glycol in the stated reason, GxRadar's search found. One record mentions ethylene glycol. It is a Class III recall, posted in December 2023, of a prescription oral solution for "high content of ethylene glycol" in an excipient. How FDA tracks the excipients in approved drugs is covered in our guide to the Inactive Ingredient Database, and recall counts by class and year are on our recalls page. FDA's guidance asks that every container of every lot be checked against a limit of 0.10 percent.