The influenza vaccine, while not perfect, significantly decreases the risk of catching the annual flu epidemic. It may also lead to less severe symptoms if influenza does develop.
A double-blind study of 227 individuals found that ginseng might help the vaccine work more effectively, increasing antibody production and decreasing the frequency of colds and flus.
The dose used in the study was 100 mg of Asian ginseng
taken twice daily for 1 month prior and 2 months after the vaccine was administered.
Scaglione F, et al. Efficacy and safety of the standardised ginseng extract G115 for potentiating vaccination against the influenza syndrome and protection against the common cold.
Drugs Exp Clin Res
22(2): 65–72, 1996.