This is a single-center, randomized, double-blind, placebo-controlled clinical trial evaluating the efficacy and safety of a white ginseng extract (KoreaGinseng F Max) for improving blood circulation in adults with poor peripheral blood flow.

A total of 100 adults aged 20 to under 65 years with platelet aggregation above 55% will be enrolled and randomly assigned in a 1:1 ratio to receive either the white ginseng extract or a matching placebo for 8 weeks. Each participant takes 3 tablets after breakfast and 3 tablets after dinner (6 tablets per day).

The main goal is to measure the change in ADP-induced platelet aggregation from baseline (Visit 2) to the end of treatment (Visit 4, Week 8). The study also assesses effects on coagulation measures, blood lipids, serotonin, blood pressure, white blood cell count, and overall safety.

Study design: Single-center, randomized, double-blind, placebo-controlled, parallel-group interventional trial.

Population: Men or women aged ≥20 and <65 years requiring improvement of blood circulation, with ADP- and collagen-induced platelet aggregation above 55%, who provide written informed consent.

Intervention: Participants are randomized 1:1 to the test product (white ginseng extract, KoreaGinseng F Max) or a matching placebo control. Dosing is 3 tablets after breakfast and 3 tablets after dinner (6 tablets/day) for 8 weeks, taken orally.

Visit schedule: Screening (Visit 1, Week -2 to 0); randomization/baseline (Visit 2, Week 0); interim visit (Visit 3, Week 4 ±5 days); end-of-treatment (Visit 4, Week 8 ±5 days); plus a supplementary visit if needed.

Primary endpoint: Change in ADP-induced platelet aggregation from baseline (Visit 2) to Visit 4.

Secondary endpoints: Percent change in ADP-induced platelet aggregation; change and percent change in prothrombin time and activated partial thromboplastin time; change in serum lipids (total cholesterol, HDL-C, LDL-C, triglycerides); change in serotonin; change in systolic and diastolic blood pressure; and - all from baseline to Visit 4.

Sample size: 100 participants (2 groups); approximately 50 evaluable per group, accounting for an ~8% dropout rate.

Inclusion Criteria:

• Men or women aged 20 to under 65 years
• Platelet aggregation response above 55% (satisfied for both collagen and ADP)
• Provides voluntary written informed consent to participate

Exclusion Criteria:

• History of hypersensitivity or allergy to ginseng-containing products that may affect the results
• Surgery under general anesthesia within 12 weeks before participation
• Use of contraindicated products such as red ginseng or omega-3 fatty acids within 2 weeks before screening
• Use of antiplatelet drugs such as aspirin within 2 weeks before screening (subjects on prophylactic aspirin <100 mg with unchanged dose/method may participate)
• Uncontrolled hypertension not managed by medication (systolic BP >160 mmHg or diastolic BP >97 mmHg)
• Currently using study-indicated medications such as those for dyslipidemia or diabetes
• On drug treatment with a history of peripheral atherosclerosis and coronary artery disease (peripheral vascular disease, abdominal aortic aneurysm, carotid artery disease)
• Coronary artery bypass surgery, vascular anastomosis, pacemaker use, myocardial infarction, heart failure, arrhythmia, or other cardiac disease within 6 months
• Infectious inflammatory disease, systemic infection, immune-resistance-related disease, or leukemia (blood cancer)
• Irritable bowel syndrome, gastrointestinal resection surgery, or GI-related disease such as Crohn's disease
• History of cerebral ischemia or cerebral hemorrhage such as cerebral infarction or stroke due to atherosclerosis
• Concurrent symptoms of myocardial infarction, atherosclerosis, or congestive heart failure
• Clinically significant liver dysfunction (ALT or AST ≥2.5x the upper limit of normal)
• Clinically significant renal dysfunction (serum creatinine >2.0 mg/dL)
• TSH outside 0.27-5.07 microIU/mL or thyroid disease
• History of, or current treatment for, psychiatric/neurological disorders including schizophrenia, depression, or drug addiction
• History of malignant tumor within 5 years before screening
• Pregnant or breastfeeding women, women of childbearing potential not using medically reliable contraception, or women within 6 months postpartum
• Alcohol consumption within the last 3 days (men 30 g/day, women 20 g/day)
• Participation in another clinical trial within 4 weeks before participation
• Subjects judged unsuitable by the investigator or other physicians