Allergic cutaneous vasculitis （ACV） is a hypersensitivity disorder characterized by chronic progression and frequent relapses. Professor Cao Yemin believes that its pathogenesis primarily involves a deficiency of yang at the root and toxin in the collaterals as the manifestation. The treatment should address both the root causes and symptoms， combining systemic and local approaches， primarily supporting the spleen and kidney yang， while also clearing toxic heat from the collaterals. He proposes an academic view that "pathogens invade due to underlying deficiencies， leading to stasis caused by these pathogens. Supporting the body's healthy qi is fundamental， while expelling pathogens takes precedence." He advocates for stage-specific differentiated diagnosis. Treatment is divided into two stages： an acute progressive stage， where expelling pathogens is prioritized with an emphasis on clearing and cautious use of blood-activating medicinals； and a recovery and remission stage， where the body's healthy qi remains weak and residual pathogens persist， focusing on supporting the healthy qi and consolidating the foundation with a balanced approach that combines both expelling and tonifying methods. Throughout the treatment， Professor Cao applies the Heying （harmonizing ying level） method， supplemented by methods to clear heat， boost qi， and harmonize blood. Clinically， he often uses traditional Chinese herbal medicines that clear heat， remove toxicity， and regulate immune functions， gradually reducing the dosage of steroid medications， thereby enhancing clinical outcomes. A proven case is included.