医 (traditional 醫) shows an arrow 矢 in an open box 匚 — the surgeon's work of removing arrowheads, the oldest emergency medicine. The traditional form added a hand with a lance and a wine-jar of antiseptic; the simplified form kept the arrow being boxed away.
医 heals the vocabulary: 医生 (doctor — 'medicine-life person', with 生), 医院 (hospital), 中医 (traditional Chinese medicine) versus 西医 (Western medicine). China runs both systems side by side — herbs and acupuncture down the hall from MRI machines. The saying 医者仁心 ('healers have benevolent hearts') is the profession's Confucian oath.
An arrow 矢 pulled out and boxed 匚 — MEDICINE.
中医 (TCM) and 西医 (Western medicine) coexist in Chinese hospitals — patients often see both for one illness.