The following is a summary of “Shortages of Antimuscarinic Delirium Treatments: Impact and Implications,” published in the May 2023 issue of Emergency Medicine by Whitledge et al.

Antimuscarinic delirium (AD), a potentially fatal condition encountered frequently by emergency clinicians, results from antimuscarinic agent poisoning. The mainstays of pharmacotherapy are physostigmine and benzodiazepines; dexmedetomidine and non-physostigmine centrally-acting acetylcholinesterase inhibitors (cAChEi) such as rivastigmine have also been described. These medications are unfortunately subject to drug shortages, which hinder the ability to provide appropriate pharmacologic treatment for AD patients. From January 2001 to December 2021, data on drug shortages were retrieved from the University of Utah Drug Information Service (UUDIS) database. The researchers are examining deficiencies of first-line and second-line treatments for Alzheimer’s disease (physostigmine and parenteral benzodiazepines and dexmedetomidine and non-physostigmine cAChEi, respectively). The following information was extracted: drug class, formulation, route of administration, the reason for the shortage, duration of need, generic status, and whether the drug was a single-source product (made by only one manufacturer).

The researchers calculated shortage overlap and the median duration of shortages. From January 1, 2001, to December 31, 2021, the UUDIS was notified of twenty-six drug shortages affecting AD treatments. The median duration of medication shortages across all classifications was six months. Four deficiencies still needed to be addressed after the study period. Dexmedetomidine was the medication most frequently in short supply, while benzodiazepines were the most frequently in short supply as a class. Twenty-five shortages involved parenteral formulations of rivastigmine, and one deficiency involved the transdermal patch formulation. Most (88.5%) of needs involved generic medications, while fifty percent (50%) of the shortages involved single-source products. Most (27%) reported shortages were due to manufacturing issues. In 92% of instances, shortages overlapped in time with other needs. 

Deficiencies were frequently protracted. The frequency and duration of shortages increased in the second half of the study period. During the study period, the needs of agents used to treat AD were common and affected all agent classes. Frequently, shortages were prolonged, and multiple shortages persisted after the study period. Significant concurrent needs involving various agents have occurred, which may impede the effectiveness of substitution to mitigate the shortage. To reduce future deficits of drugs used for the treatment of AD, healthcare stakeholders must develop innovative patient- and institution-specific solutions in times of shortage and work to build resilience into the medical product supply chain.

Source: sciencedirect.com/science/article/abs/pii/S0735675723001043