This article is for informational purposes only. The current coronavirus outbreak is an ongoing event and certain details may change as new information comes to light. No effective or FDA-approved products are currently available for the treatment of the new coronavirus (also known as SARS-CoV-2 or 2019-nCoV), although research is still ongoing.
Ginseng is a plant found in North America and eastern Asia. There are many different types of ginseng, such as American ginseng, Korean red ginseng, Indian ginseng, and Siberian ginseng. American ginseng is a very popular variety [1, 2].
Flu and Other Respiratory Infections
In a trial of 227 people, those who took 100 mg of an Asian ginseng extract (G115) were less likely to catch a cold or flu. The ginseng group also had higher levels of NK cell activity [3].
In another trial on 100 people, Asian ginseng reduced the incidence and severity of upper respiratory infections [4].
In mice, Asian ginseng, its fermented extracts, and compounds (saponins and polysaccharides) increased survival after infection with different influenza viruses [5, 6, 7, 8, 9] and enhanced the effectiveness of the vaccines against them [10, 11, 12].
In mice infected with respiratory syncytial virus (RSV), ginseng extract (both oral and as a nose spray) reduced lung damage, improved lung viral clearance, increased the proliferation of T cells and dendritic cells, and reduced weight loss [13, 14, 15].
Similarly, different American ginseng extracts helped prevent respiratory tract infections in 5 clinical trials on almost 1,700 people. However, some of these studies were funded by a company that sells the extract, which indicates a potential conflict of interest [16, 17, 18, 19, 20].
Additionally, a meta-analysis warned that the evidence to support this use was insufficient due to the differences in the population samples and qualities of the studies [21].
COPD and Lung Damage
According to a review of 12 studies involving 1,560 COPD patients, Asian ginseng may improve the quality of life and lung function and enhance the effectiveness of drug treatments. However, the authors warned that most studies carried out up to then (2011) had a high risk of bias [22].
In line with this, the latest clinical trial with Asian ginseng failed to find any benefits over placebo in people with COPD [23].
In rats with COPD, the saponin ginsenoside Rg1 improved lung function and prevented structural changes associated with this condition [24, 25, 26].
This and other ginseng saponins also relieved cell death, inflammation, and oxidative damage in rats with acute lung injury [27, 28, 29, 30].
A TCM injection with Asian ginseng and ophiopogon root (Shenai) prevented airway muscle cell death in rats with emphysema [31].
Asthma
In asthmatic mice, ginseng extract reduced airway inflammation. An extract combining red ginseng and Salvia plebeia had similar results. However, the anti-inflammatory activity may have been mostly due to Salvia plebeia, since its component nepetin was also effective [32, 33].
The Shenai injection prevented the excessive proliferation of airway muscle cells in asthmatic rats [34].
Other Viral Infections
Asian ginseng extract, as an add-on to antivirals, reduced liver tissue scarring markers in a small trial on 38 people with hepatitis B [35].
In mice infected with coxsackievirus B3, ginseng saponins reduced viral load and the severity of heart muscle inflammation [36, 37].
Asian ginseng extract protected female mice against vaginal herpes infection, possibly by increasing IFN-γ secretion [38].
Two ginsenosides from Asian ginseng reduced infection rates and diarrhea in mice challenged with rotavirus [39].
In piglets challenged with the porcine reproductive and respiratory syndrome virus, several saponins from ginseng improved survival and reduced lung injury, fever, weight loss, anemia, internal inflammation, and viral load. These saponins also reduced the damage caused by porcine circovirus 2 in mice [40, 41, 42].
In cell-based studies, ginseng extracts and their components inhibited the following viruses:
- Influenza (H1N1, H3N2, H5N1, H7N9, and H9N2) [6, 43]
- Rhinovirus 3 [44]
- Hepatitis A [45]
- Herpes simplex 1 and 2 [46, 47]
- HIV [48]
- RSV [13, 14]
- Bursal disease virus [49]
- Coxsackievirus B3 [36, 44]
- Enterovirus 71 [44]
- Rotavirus [50]
- Porcine reproductive and respiratory syndrome virus [40].
Immune Boosting
Evidence suggests that ginseng boosts immune function. Those taking red ginseng powder during chemotherapy treatment had a higher 5-year disease-free survival and overall survival rate in a study on 42 people [51].
In another trial on 96 people with lung cancer, ginseng carbohydrates enhanced the immune function by increasing Th1 cytokines (IFN-gamma and IL-2) while reducing Th2 cytokines (IL-4 and IL-5) [52].
Ginseng extract also increased survival in patients with HIV, possibly by slowing the decrease in CD4+ T cell count, in a trial on over 250 people [53].
Vaccine Enhancement
Ginseng stem‐leaf saponins, both alone and in combination with selenium, enhanced the effects of a combined vaccine against the coronavirus infectious bronchitis virus (IBV) and the virus that causes Newcastle disease (NDV) in chicken. These saponins also enhanced the vaccine against infectious bursal disease [54, 55, 56, 57].
Ginseng extract, combined with either selenium or thimerosal, enhanced the immune response in mice vaccinated against pseudorabies. A saponin isolated from ginseng (ginsenoside Re) had similar effects [58, 59, 60, 61].
Similarly, its combination with rapeseed or mineral oil enhanced the immune effects of the foot-and-mouth disease vaccine in mice [62, 63].
The Rb1 fraction of ginseng enhanced the effectiveness of the vaccine against porcine parvovirus in mice [64].
In horses vaccinated against equid herpesvirus 1, low-dose ginseng increased antibody production [65].
