Sophora flavescens (commonly known as Ku Shen) is a traditional herb used in Chinese medicine. Its primary documented uses have focused on clearing heat, drying dampness, and treating conditions such as dysentery, skin disorders, and certain parasitic infections. In traditional Chinese medicine (TCM), herbs are sometimes used in multi-herb formulas to treat upper respiratory symptoms, including sinus congestion, but Sophora flavescens is not a primary or common herb for this indication. Its main actions are as an anti-inflammatory, anti-bacterial, and anti-parasitic agent; occasionally, these properties may be referenced in multi-herb formulas addressing respiratory conditions.

Scientific research has focused on the herb's potential in treating certain infections, inflammation, and even cancer, but there is little to no direct clinical or pharmacological evidence supporting its use specifically for sinus congestion. No randomized controlled trials or high-quality studies have evaluated its efficacy for sinus or nasal congestion in humans. Therefore, while some traditional applications may include it as a minor component of broader respiratory formulas, evidence is weak, and its use for sinus congestion is based mainly on traditional theory rather than modern validation.