Recent events have highlighted the serious risks posed by the contamination of medicines with diethylene glycol (DEG) and ethylene glycol (EG), particularly in children. A notable case occurred between June and September 2022 in Gambia, where children developed acute renal failure after being administered medicines that were later found to contain DEG and EG. This led to a rapid public health response, including the suspension of the use of all paracetamol and promethazine syrups and a recall of the contaminated products. The World Health Organisation (WHO) issued a global alert on the affected medicines from Maiden Pharmaceuticals Limited, India. Investigations directly linked the Acute Kidney Injury (AKI) cases to the contaminated syrups, emphasising the critical importance of strict quality management in the manufacture and regulation of medicines.
The WHO has called for urgent action following reports of over-the-counter cough syrups for children contaminated with high levels of DEG and EC in at least seven countries, resulting in more than 300 deaths. These incidents underscore the need for immediate and coordinated action by all stakeholders in the medical supply chain, including regulators, manufacturers, suppliers and distributors, to detect and eliminate substandard medical products, ensure the approval and safe sourcing of medical products, and improve surveillance and risk-based inspections.
In response to these concerns, the US Food and Drug Administration (FDA) has issued new guidance for the pharmaceutical industry on testing for EGs and DEGs in high-risk drug components. This guidance was prompted by WHO global health alerts about contaminated drugs in countries such as Indonesia, Gambia and Uzbekistan. EG and DEG are highly toxic substances used in industrial applications such as antifreeze and should never be included in medicines. Their contamination in liquid oral drugs has been linked to serious health consequences, including central nervous system (CNS), heart and kidney damage and even death. The FDA guidance aims to limit EG and DEG content in high-risk drug ingredients to no more than 0.10%, with a focus on glycerine, propylene glycol and certain sugar polyol solutions that have been contaminated in the past. This initiative emphasises the need for stringent testing and quality assurance measures in the manufacture and distribution of medicinal products.
The importance of this can also be seen in the number of warning letters issued by the FDA and the activities of other organisations such as the USP and WHO.