Efficacy of an Extract of Concentrated Korean Red Ginseng for Preventing Upper Respiratory Tract Infections

A Placebo-Controlled Trial of Korean Red Ginseng Extract to Prevent Acute Respiratory Illness in Healthy Subjects

Upper respiratory tract infections are a major source of morbidity throughout the world. Extracts of Korean red ginseng have been found to have the potential to modulate both natural and acquired immune responses. The investigators sought to examine the efficacy of an extract of Korean red ginseng in preventing colds. Therefore, the efficacy and safety of Korean red ginseng will be investigated in healthy subjects during the influenza season.

The extract of Korean red ginseng has been found efficacious in the prevention of respiratory infections in healthy adults. The investigators will be conducted a randomized, double-blind, placebo-controlled study at the onset of the influenza season. A total of 100 subjects 30-70 years of age with a history of at least 2 colds in the previous year will be recruited from the general population in jeollabuk-do, South Korea. The subjects will be instructed to take 9 capsules per day of either the Korean red ginseng extract or a placebo for a period of 12weeks. The primary outcome measure will be the number of Jackson-verified colds. Secondary outcome measures will be included symptom severity, total number of days of symptoms and duration of all colds. Cold symptoms will be scored by subjects.

Inclusion Criteria:

• Males and females 30-70 years old
• have contracted at least 2 colds in the past year

Exclusion Criteria:

• if they had been vaccinated against influenza in the previous 6 months.
• Subjects with medical conditions such as multiple sclerosis, tuberculosis, diabetes, cancer, lupus, HIV/AIDS, cardiovascular disease, hypertension, neurologic or psychiatric disease, and renal, pulmonary and hepatic abnormalities
• Subjects taking medications such as immunosuppressive drugs, corticosteroids, warfarin, phenalzine, pentobarbital, haloperidol or cyclosporine
• Abnormal liver or kidney function tests (ALT or AST>2 times the upper limit of normal; elevated creatinine, males>125uM/L, females>110uM/L)
• pregnant or lactating women and heavy smokers.
• being judged by the responsible physician of the local study center as unfit to participate in the study