One work is attributed to Gan Ruizhi, with details about his background and life being scarce. According to Sui Shu-Jingjizhi, the works authored by Gan include Yongju Ear and Eye Materia Medica Essentials in nine volumes, Materia Medica Essential Formulas in three volumes, Essential Formulas for Treating Yongju and Metal Wounds in fourteen volumes, and Formulas for Treating Ear and Eye Diseases. Gan was a physician specializing in external diseases and otolaryngology during the Six Dynasties period, a time when specialized works on external diseases of the ear and eye were already being published.