Recruiting · registry status

Measuring the response to a dose of levodopa

This study investigates movement responses to levodopa in Parkinson's and related conditions under supervised testing.

Testing a treatment or activity · Study reference: JPRN-UMIN000007896

Plain-language introduction written with AI from the registry; not independently checked by a clinician. Read the original details below ↓

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Start (reported date): 2012-05-01

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No results summary has been confirmed in the registry records we imported. See connected papers below; we keep checking after recruitment ends.

Changes we have recorded

2026-10-11 — recruiting

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Papers connected to this study

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Who can join?

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Sex eligibility reported by registry: male and female

Inclusion criteria: A consecutive series of patients admitted to our hospital for diagnostic and/or treatment purpose, who presented with extrapyramidal symptoms Exclusion criteria: None

Full study name & original research details

Official study title

Levodopa challenge test for Parkinson's disease and other parkinsonian syndromes - Levodopa challenge test for Parkinson's disease and other parkinsonian syndromes

Short title used by the registry

Levodopa challenge test for Parkinson's disease and other parkinsonian syndromes

Original description

Intervention: The patients are given domperidone 30 mg/day for 3 days. When a patient is already on any anti-parkinson drugs, these drugs were withdrawn from the night before of the evaluation day. On the fourth day lactose powder is given to the patients and levodopa (250 mg)/carbidopa (25 mg) is given on the fifth day in a double-blind manner. On fourth and fifth day, motor symptoms of the patients are examined using the Unified Parkinson's Disease Rating Scale motor scores by a clinician who is blind to the test drug. The patients are given domperidone 30 mg/day (standard dose in Japan) for 3 days. When a patient is already on any anti-parkinson drugs, these drugs were withdrawn from the night before of the evaluation day. On the fourth day levodopa (250 mg)/carbidopa (25 mg) is given to the patients and lactose powder is given on the fifth day in a double-blind manner. Motor symptoms of the patients are examined using the Unified Parkinson's Disease Rating Scale motor scores by a clinician who is blind to the test drug. Primary outcome: The improvement of Unified Parkinson's Disease Rating Scale motor scores

Conditions reported: Parkinson's disease and other parkinsonian syndromes

Registry records for this study

Records are joined using registration identifiers. Titles alone do not establish that two studies are the same.

JPRN · JPRN-UMIN000007896 ↗ — Recruiting; WHO ICTRP processed 2026-06-29; checked 2026-10-14

Study type: Interventional
Interventions: The patients are given domperidone 30 mg/day for 3 days. When a patient is already on any anti-parkinson drugs, these drugs were withdrawn from the night before of the evaluation day. On the fourth day lactose powder is given to the patients and levodopa (250 mg)/carbidopa (25 mg) is given on the fifth day in a double-blind manner. On fourth and fifth day, motor symptoms of the patients are examined using the Unified Parkinson's Disease Rating Scale motor scores by a clinician who is blind to the test drug. The patients are given domperidone 30 mg/day (standard dose in Japan) for 3 days. When a patient is already on any anti-parkinson drugs, these drugs were withdrawn from the night before of the evaluation day. On the fourth day levodopa (250 mg)/carbidopa (25 mg) is given to the patients and lactose powder is given on the fifth day in a double-blind manner. Motor symptoms of the patients are examined using the Unified Parkinson's Disease Rating Scale motor scores by a clinician who is blind to the test drug.
Phases: Not selected
Sponsor: Kansai Medical University
Start date reported by registry: 2012-05-01 (reported)

Registry updated: Not reported · Status last verified by the registry submitter: Not reported

Registry records retrieved 2026-10-14 (UTC). Individual records may have older updates. Recruitment and eligibility must be confirmed with the study team.

Contact the research team

Public study contacts supplied to the registry. Ask whether recruitment is still open and what participation involves.

Hirofumi Kusaka, Reika Wate

Study locations

Site status can differ from overall study status. “Status not reported” means local availability needs confirmation. Remote participation and travel arrangements must be checked with the team.

Facility not reported

Japan

Status not reported

The original descriptions and participation rules come from the registry. Participation is voluntary and does not guarantee benefit.