Recalls of some batches of metformin have occurred due to the detection of N-nitrosodimethylamine (NDMA) in amounts above the acceptable intake (AI) of 96 ng per day. Prior to the recalls, an international regulatory laboratory network had been monitoring drugs for nitrosamine impurities with each laboratory independently developing and validating multiple analytical procedures to detect and measure nitrosamines in metformin drugs used in their jurisdictions. Here, we provide an overview of the analysis of metformin active pharmaceutical ingredients (APIs) and drug products with 1090 samples (875 finished dosage forms (FDFs) and 215 API samples) tested beginning in November of 2019 through July of 2020. Samples were obtained internationally by a variety of approaches, including purchased, received from firms via information requests or selected by regional regulatory authorities (either at wholesalers or during GMP inspections). Only one nitrosamine (NDMA) was detected and was only present in some batches of metformin products. For API samples, 213 out of 215 lots tested had no measurable level of NDMA. For FDF samples tested, the number of batches with NDMA above the AI amount for patient safety was 17.8% (156/875). Based on these data, although the presence of NDMA was of concern, 82.2% of the samples of metformin drug products tested met quality and safety standards for patients. Regulatory agencies continue to collaborate extensively and work with marketing authorization holders to understand root causes of nitrosamine formation and agree on corrective actions to mitigate the presence of NDMA in future metformin batches. Graphical abstract

In recent years, an increasing number of case reports have mentioned the presence of illicit nootropics, smart drugs or mind doping products on the market. To better understand the extent of the problem, a market surveillance study was organised by the General European Official Medicines Control Laboratory Network and associated member Australia to detect substandard, falsified or illegal medicines or dietary supplements containing unauthorised nootropic molecules of natural or synthetic origin. From January 2020 to September 2024, 159 different samples were documented, which yielded a comprehensive dataset of 166 molecular identification entries. Within this dataset, 34 distinct molecules were identified. Most samples were sold or presented as dietary supplements (49%) or medicines (32%). The vast majority (69%) were collected from the illegal market. Prescription drugs and non-authorised drugs only available on prescription in Russia were found in pharmacological quantities; some of the latter (noopept, phenylpiracetam and phenibut) were intercepted as large bulk quantities of raw material. Unauthorised novel foods, prescription or higher amounts of melatonin, and clinically uncharacterised research molecules were also reported. This study highlights the need for more active monitoring and screening of such products, as consumption of some of the reported samples could have detrimental health effects. Furthermore, as a large number of the samples were presented as dietary supplements, consumers may not be aware of the possible dangers and side-effects of these products.