We report six patients who had dermatitis after contacting certain chemical substances (one worker with contact 1-chloromethyl naphthalene and five with contact Hydroxy-phthalimide). They appeared like drug-induced erythma multiforme, bullosa epidermalysis from the point of contact gradually spreading to the whole body, combining high temperature, digestive system dysfunction, such as liver dysfunction etc. We can call this occupational drug-induced medicamentosa. The course of dermatosis diseases is 1 - 2 months. Hormone and sustaining treatment may be effective. We discuss chemistry substance, clinical presentation, diagnoses, treatment and relevant prognosis.