Prescription Trends for ADHD Medications in Japan, 2018-2023
Author(s)
Ryutaro Suzuki, MD1, Ryosuke Kumazawa, PhD2, Manabu Akazawa, MPH, PhD2, Ken INADA, MD, PhD1.
1Department of Psychiatry, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan, 2Department of Public Health and Epidemiology, Meiji Pharmaceutical University, Kiyose, Tokyo, Japan.
1Department of Psychiatry, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan, 2Department of Public Health and Epidemiology, Meiji Pharmaceutical University, Kiyose, Tokyo, Japan.
OBJECTIVES: To investigate prescription patterns for attention-deficit/hyperactivity disorder (ADHD) medications in Japan following the market availability of methylphenidate, lisdexamfetamine, atomoxetine, and guanfacine.
METHODS: Analysis of health insurance claims data (DeSC Healthcare) for patients aged 0-17 years diagnosed with ADHD who received medication between April 2018 and August 2023. For each medication, we investigated the overall prescription rate, the rate of combined prescriptions, and the rate of prescriptions for new patients, by sex, age, and medical specialty using Jonckheere-Terpstra trend test.
RESULTS: Guanfacine prescriptions increased significantly (19.3% to 46.4%, P<0.001) from 2018 to 2023, while methylphenidate (64.7% to 47.5%, P<0.001) and atomoxetine (34.4% to 22.4%, P<0.001) prescriptions declined. Lisdexamfetamine, introduced in late 2019, reached 5.2% of prescriptions by 2023. Guanfacine became predominant for females after 2021 and for the 6-12 age group, while methylphenidate remained dominant in the 13-17 age group. In psychiatric departments, guanfacine emerged as the most prevalent prescription, while methylphenidate dominated in non-psychiatric settings. For new prescriptions, guanfacine increased from 27.4% to 41.3% (P=0.0021). Monotherapy rates declined slightly from 82.3% to 79.6% (P=0.0011), with methylphenidate-guanfacine combination becoming the preferred option.
CONCLUSIONS: A significant shift toward guanfacine in ADHD treatment occurred in Japan, particularly among females, younger children, and in psychiatric settings. This trend may be attributed to guanfacine's lack of distribution regulations, once-daily administration, and unique pharmacological mechanism. With unit costs ranging from $1.57-$1.83 (methylphenidate), $0.60-$1.14 (atomoxetine), $2.66-$3.51 (guanfacine), to $4.40-$4.88 (lisdexamfetamine), medication cost increases are anticipated, necessitating future cost-effectiveness evaluation.
METHODS: Analysis of health insurance claims data (DeSC Healthcare) for patients aged 0-17 years diagnosed with ADHD who received medication between April 2018 and August 2023. For each medication, we investigated the overall prescription rate, the rate of combined prescriptions, and the rate of prescriptions for new patients, by sex, age, and medical specialty using Jonckheere-Terpstra trend test.
RESULTS: Guanfacine prescriptions increased significantly (19.3% to 46.4%, P<0.001) from 2018 to 2023, while methylphenidate (64.7% to 47.5%, P<0.001) and atomoxetine (34.4% to 22.4%, P<0.001) prescriptions declined. Lisdexamfetamine, introduced in late 2019, reached 5.2% of prescriptions by 2023. Guanfacine became predominant for females after 2021 and for the 6-12 age group, while methylphenidate remained dominant in the 13-17 age group. In psychiatric departments, guanfacine emerged as the most prevalent prescription, while methylphenidate dominated in non-psychiatric settings. For new prescriptions, guanfacine increased from 27.4% to 41.3% (P=0.0021). Monotherapy rates declined slightly from 82.3% to 79.6% (P=0.0011), with methylphenidate-guanfacine combination becoming the preferred option.
CONCLUSIONS: A significant shift toward guanfacine in ADHD treatment occurred in Japan, particularly among females, younger children, and in psychiatric settings. This trend may be attributed to guanfacine's lack of distribution regulations, once-daily administration, and unique pharmacological mechanism. With unit costs ranging from $1.57-$1.83 (methylphenidate), $0.60-$1.14 (atomoxetine), $2.66-$3.51 (guanfacine), to $4.40-$4.88 (lisdexamfetamine), medication cost increases are anticipated, necessitating future cost-effectiveness evaluation.
Conference/Value in Health Info
2025-09, ISPOR Real-World Evidence Summit 2025, Tokyo, Japan
Value in Health Regional, Volume 49S (September 2025)
Code
RWD120
Topic Subcategory
Health & Insurance Records Systems
Disease
SDC: Mental Health (including addition)