This document provides a behavioral materia medica for the homeopathic remedy Carcinosin. It describes Carcinosin patients as having the following key characteristics: sensitive, romantic, passionate personalities; a perfectionist and rebellious nature; attraction to rhythm, music, and the arts; and unintegrated opposites within their nature like being both courteous and fastidious yet also destructive. Their mental states are often affected by unhappy childhood experiences involving emotional suppression, fear, fright, anticipation or feelings of being trapped.