Associating regulatory actions on diclofenac use with Danish trends in utilization by route of administration 1999-2023.

Aims: With the growing evidence of cardiovascular risks associated with diclofenac use, regulatory measures governing its application and sales have intensified since 2008. We evaluated the association between central regulatory actions and trends in diclofenac use in Denmark from 1999 to 2023, according to different dosage forms and routes of administration.

Methods and results: Data on diclofenac sales in Denmark from 1999 to 2023 were retrieved from the publicly available web database MEDSTAT, based on the Danish Register of Medicinal Products Statistics. The annual sales of various diclofenac dosage forms, including systemic (tablets, modified-release dosage forms, and suppositories) and topical (nonspecific and ophthalmic) dosage forms, were calculated and displayed by sales unit. From 1999 to 2008, sales of all systemically administered diclofenac forms increased: tablets by 51% (2000-2008), modified-release dosage forms by 40% (2003-2007), and suppositories by 44% (1999-2008). Thereafter, sales of tablets declined by 86% and modified-release dosage forms by 90% through 2023. The sales of suppositories declined somewhat lesser, by 34%, during 2008 to 2018 and then increased by 67% through 2023. Sales of nonspecific topical diclofenac increased by several thousandfold from 2005, although with brief periods of decline.

Conclusion: Sales of systemically administered diclofenac dosage forms, particularly tablets and modified-release drugs, declined by approximately 90% from about 2008 to 2023, indicating compliance with Danish and international regulatory actions. Conversely, sales of topically administered diclofenac increased heavily from 2005 to 2023, denoting a policy-driven shift toward these lower risk dosage forms.