Use of Methenamine Hippurate in an Ageing Population: National Prescription Trends from Norway (2004-2020)

To describe national trends in methenamine hippurate prescribing in Norway, including variations by age and sex.

Data were extracted from the Norwegian Prescription Database for 2004-2020. Methenamine hippurate was identified using ATC code J01XX05. All prescriptions were included; no exclusion criteria were applied. Outcomes included number of users, prevalence per 1000 persons, and distribution by age and sex. Analyses were descriptive.

From 2004 to 2020, use of methenamine hippurate increased steadily, with an average annual rise of 5.3%, reaching 35,134 unique users in 2020. Overall prevalence increased from 3.8 to 6.5 per 1000 persons. Women accounted for most users throughout; female prescribing increased from 5.5 to 11.3 per 1000 persons, while male use rose modestly from 1.3 to 1.8 per 1000 persons. The proportion of male users declined from 18.8% to 13.8%. Use was strongly age dependent: individuals aged ≥80 years accounted for around 60% of users. In 2020, rates peaked among women aged >90 years (64.9 per 1000) versus 25.8 per 1000 among men of the same age. Marked regional variation was observed, with higher use in northern and rural regions.

Methenamine hippurate use in Norway has increased substantially, driven mainly by rising use among older women. Although prescribed less frequently, use among men persists. This trend may reflect increased awareness of the burden of recurrent urinary tract infections and a shift towards non-antibiotic prophylaxis. Further research is needed to evaluate prescribing appropriateness, clinical effectiveness, and implications for antimicrobial stewardship.