Help for Upper Respiratory Tract Infections

Experts say that there is not yet enough evidence to prove astragalus can prevent or treat upper respiratory infections. ¹³²

However, astragalus does boost the immune system, and research suggests that astragalus combined with other herbs may help. By itself, astragalus could also be useful in preventing respiratory infections in patients with conditions that tax their immune system. ¹³³

For example, in one clinical study 34 patients were given weekly injections containing astragalus and angelica for two months. Results showed the herbal formulas was over 88% effective in cold prevention. ³⁸

Recently researchers conducted a large study involving almost 800 patients. All of the patients suffered from infections resistant to drug treatment. Results showed that treatment with herbal medicine containing astragalus and antibiotics was much more effective than antibiotics alone. ¹³⁴

How Does Astragalus Work Against Respiratory Infections?

Immune Boosting Benefit of Astragalus

Astragalus stimulates the spleen, an organ with important immune system functions. The spleen is essential to immune system protection against bacteria that can cause meningitis and pneumonia. ^23, 100

Research shows that astragalus also activates and stimulates the production of immune cells. This activity can help the body resist colds and influenza. Additionally, astragalus increases production of a key antimicrobial protein in cells that line the respiratory system. ^98, 135

Antibacterial and Antiviral Effects of Astragalus

Lab studies indicate that astragalus shows potent antiviral activity against the bird flu virus (H1N1). This may prove to be especially useful as drug-resistant forms of the flu virus continue to emerge. ⁴⁹