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

Patrick Juliebø-Jones,1,2 Bhaskar K Somani,3 Christian Beisland1,2 1Department of Urology, Haukeland University Hospital, Bergen, Norway; 2Department of Clinical Medicine, University of Bergen, Bergen, Norway; 3Department of Urology, University Hospital Southampton, Southampton, UKCorrespondence: Patrick Juliebø-Jones, Department of Urology, Haukeland University Hospital, Bergen, Norway, Tel +47 55 97 50 00, Email [email protected]: To describe national trends in methenamine hippurate prescribing in Norway, including variations by age and sex.Methods: 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.Results: 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.Conclusion: 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.Plain Language Summary: Recurrent urinary tract infections are common and can be very troublesome, especially for women. One way to prevent repeated infections is a medicine called methenamine hippurate, which is not an antibiotic and has been used for many years.We looked at all prescriptions of this medicine in Norway from 2004 to 2020. Over this time, the number of people using methenamine hippurate almost doubled. It was used much more often by women than by men, and it was most common in older people, especially those over 80 years of age. The highest use was seen in very old women.Use of the medicine increased in all parts of Norway, but it was more common in northern and rural areas than in large cities like Oslo.Overall, this study shows that methenamine hippurate is being used more and more in Norway, mainly among older women, but it is also still used in men.Keywords: urinary infection, UTI, recurrent, antiseptic, antibiotic, prophylaxis