This is a prospective, multicenter, randomized, double-blinded, placebo-controlled, parallel-group, clinical trial to explore the effectiveness of an herbal medication, Gongjin-dan (GJD) for chronic dizziness (Ménière disease, psychogenic dizziness, or dizziness of unknown cause), identified as liver-deficiency pattern/syndrome, and assessed with Dizziness Handicap Inventory (DHI) ≥ 24 at baseline. Participants will be randomized and allocated to either GJD or placebo group with 1:1 ratio and orally administered GJD or placebo pills once a day for 8 weeks. For collecting data for cost-effectiveness analysis, the participants will be followed up to 12 months from randomization.

Inclusion Criteria:

1. Age between 20 and 79 years, of either sex
2. Dizziness originating from Ménière disease, psychogenic cause, or unknown cause
3. Recurring symptom of dizziness for more than 1 month
4. Dizziness Handicap Inventory (DHI) score ≥ 24 at baseline
5. Liver-deficiency pattern/syndrome identified by Traditional Korean Medicine doctors
6. Willingness to provide written informed consent

Exclusion Criteria:

1. Dizziness attributable to vestibular disorders (e.g., benign paroxysmal positional vertigo, peripheral vestibulopathy, labyrinthitis, vestibular neuronitis, and others)
2. Dizziness attributable to central nervous system (CNS) disorders (e.g., cerebellar ataxia, stroke, demyelination, vertebrobasilar insufficiency, seizure, increased intracranial pressure, Parkinson's disease, migraines, and others)
3. Cervicogenic dizziness
4. Dizziness attributable to cardiovascular disorders (e.g., arrhythmia, heart valvular disease, anemia, orthostatic hypotension, coronary artery disease, and others)
5. Any active or uncontrolled disease that might cause dizziness (e.g., uncontrolled diabetes mellitus, hypertension, respiratory or endocrinological disorders, and others)
6. Dizziness attributable to medication side effects
7. Severe chronic or terminal diseases (malignant cancer, tuberculosis, and others)
8. Intake of other antivertiginous drugs that cannot be discontinued
9. Following physiotherapy, manual therapy (e.g., vestibular rehabilitation), and/or cognitive behavioral therapy for the treatment of dizziness
10. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), or creatinine > 3 × upper limit of normal range at baseline
11. Women of (suspected) pregnancy or breast-feeding
12. Allergic reactions to the study medications
13. Suspicion of alcohol and/or drug abuse
14. Enrollment in another clinical study presently or within 30 days prior to the initial administration of the study medications
15. Difficulty in reliably communicating with the investigators or likelihood of inability to follow instructions
16. Other reason for ineligibility of participation