Objectives Drug shortages are of increasing concern to worldwide public health. The consequences of drug shortages for patient safety have been little studied, especially from a pharmacovigilance point of view. In this context, the network of French pharmacovigilance centres conducted the CIRUPT study (Conséquences Iatrogènes des RUPTures de stock/iatrogenic consequences of drug shortages) based on a prospective campaign of adverse effects occurring in the context of drug shortage notifications.

Methods All notifications involving a shortage drug submitted to the French pharmacovigilance centres between 1 January 2020 and 30 June 2021 were collected and registered in the French national pharmacovigilance database with the standardised high level term ‘product supply and availability issues’ and with predefined keywords in the narrative section.

Results 224 cases were included, involving mainly adverse drug reactions (ADRs) (n=131/224, 59%) and medication errors (n=51/224, 23%); 29% of the cases were serious. The most represented classes of shortage drugs were: vaccines (n=78/224, 35%); drugs for acid-related disorders (H2-receptor antagonists) (n=27/224, 12%); antineoplastic agents (n=17/224, 8%); and antiepileptics (n=15/224, 7%). In 82% of cases, the involved shortage drug was the subject of information delivered to health professionals by the National Agency for the Safety of Medicines and Health Products. Drug shortages were associated with an ADR related to replacement drugs in 59% (n=131/224) of the cases, drug inefficacy in 18% (n=41/224), and/or an aggravation of the underlying disease in 11% (n=25/224).

Conclusions From a pharmacovigilance point of view, a large diversity of anatomical therapeutic classes is involved and the risk related to drug shortages is not limited to drugs registered on ‘major therapeutic interest or essential drug’ lists. Information from health agencies is not sufficient to avoid the risks, and further strategies should be developed.