Limited evidenceImmunity

Yu Ping Feng San (Jade Windscreen)

A three-herb Chinese formula (astragalus, atractylodes, siler) used to reduce the frequency of infections. Meta-analyses are positive, but they pool small, mostly unblinded Chinese trials of low methodological quality.

Evidence last reviewed: August 2026

What the science says

Recurrent respiratory infections in children Limited evidence
A meta-analysis of randomised controlled trials of Yupingfeng as adjuvant treatment for recurrent respiratory tract infections in children reported fewer and shorter infections, and a later systematic review reached a similar conclusion. Both flagged small samples, inadequate blinding and probable publication bias, so the effect size is likely inflated.
Asthma in adults Limited evidence
A systematic review and meta-analysis of Yupingfeng powder for adult bronchial asthma found improvements in symptom and lung-function outcomes when added to standard therapy, again drawing on trials with a high risk of bias.
Allergic rhinitis Limited evidence
A systematic review and meta-analysis of Yupingfeng powder combined with acupuncture in allergic rhinitis reported symptom benefit, but the co-intervention makes it impossible to separate the formula's own contribution.

Dosage & safety

Studied doseCommonly 6-12 g of granules daily in two or three divided doses, or a decoction of roughly 9-15 g astragalus with smaller amounts of the other two herbs. Trials used varied products and doses.

SafetyGenerally well tolerated in short-term trials. Astragalus is an immune stimulant in laboratory models, so caution is advised for people on immunosuppressants or with autoimmune disease. Product quality varies and adulteration of Chinese patent medicines has been documented. Avoid during acute fever according to traditional practice, and consult a professional in pregnancy.

Scientific references

Adjuvant Treatment with Yupingfeng Formula for Recurrent Respiratory Tract Infections in Children: A Meta-analysis of Randomized Controlled Trials
Song T, Hou X, Yu X — Phytother Res, 2016
Adjuvant treatment with yupingfeng granules for recurrent respiratory tract infections in children: A systematic review and meta-analysis
Zhang L, Wang X, Wang D — Front Pediatr, 2022
Efficacy of Yupingfeng powder in the treatment of bronchial asthma in adults: a systematic review and meta-analysis
Zhang Q, Zhang N, Zheng Y — Front Pharmacol, 2026

Where to buy

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