This study is a protocol for investigating the immediate effects of acupuncture on brain function in patients with chronic pruritus using functional near-infrared spectroscopy (fNIRS). A total of 40 participants will be randomized into a true acupuncture (verum) or sham acupuncture group. fNIRS will monitor hemodynamic activity and functional connectivity in the prefrontal cortex and motor areas of the brain. Data will be collected in three 5-minute phases: before needle insertion, while the needle is retained, and after needle removal. The primary outcome is the change in score of the Numerical Rating Scale of Itch. Secondary outcomes include degree of itch relief, immediate comfort, itch intensity, deqi scale, and expectancy of effect. The study also analyzes regional brain activation and functional connectivity. The clinical trial registration is ITMCTR2025001506.