Trends in the prescription of constipation medications in Japan (fiscal years 2019-2023): A nationwide baseline study prior to the 2023 clinical guidelines.

Clinical Snapshot

Key Findings

• P Value: Not reported in abstract

• Effect Size: Decreased DID for contact laxatives, increased DID for newer constipation medications

• Primary Outcome: Prescription trends measured as defined daily doses per 1,000 inhabitants per day (DID)

• Nnt Or Sensitivity: Standardized claim ratios (SCRs) showing regional variations - highest for polyethylene glycol (FY2019) and linaclotide (FY2023)

• Confidence Interval: Not reported in abstract

Clinical Application

High feasibility for similar pharmacoepidemiological studies using national prescription databases Relevant for Australian practice given PBS listing of similar newer constipation agents; could inform TGA post-market surveillance and RACGP prescribing guidelines Patients with chronic constipation in developed healthcare systems with access to newer constipation medications

Abstract

Constipation is a common gastrointestinal disorder that markedly affects health and quality of life. In Japan, magnesium-based and contact laxatives have long been widely prescribed. Since the launch of lubiprostone in November 2012, several new agents with novel mechanisms have been introduced, and their use has increased. However, to our knowledge, no nationwide study has examined their use. This study aimed to analyze nationwide trends and regional differences in the prescription of medications for constipation. We used data from the Japanese National Health Insurance Claims and Specific Health Checkup Database Open Data from fiscal years (FYs) 2019 to 2023, covering the period when all currently available constipation medications were on the market in Japan, and prior to the inclusion of the drug selection flowchart in the Evidence-Based Clinical Guidelines for Chronic Constipation 2023. Prescription trends were evaluated using defined daily doses per 1,000 inhabitants per day (DID), and regional variations were assessed using standardized claim ratios (SCRs). The DID for contact laxatives decreased during the study period, whereas the DID for other constipation medications increased. Magnesium oxide showed the smallest regional variation, whereas polyethylene glycol and linaclotide showed the largest variations in FY 2019 and FY 2023, respectively. Throughout the 5-year period, the highest SCRs for contact laxatives were observed in Akita, Iwate, and Aomori prefectures. Our findings provide a comprehensive nationwide picture of evolving constipation treatment patterns and regional variations in Japan, establishing baseline data for evaluating the impact of guideline dissemination and evidence accumulation on clinical practice.

References

1. 1.Tanaka, H., & Ishii, T. (2026). Trends in the prescription of constipation medications in Japan (fiscal years 2019-2023): A nationwide baseline study prior to the 2023 clinical guidelines. Drug Discoveries & Therapeutics. https://doi.org/10.5582/ddt.2025.01135