This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Drug Abuse, Subject name: Forensic Medicine
[{'content': 'Chronic cocaine abuse have following features except: \nSelect and explain. \nA. Peripheral gangrene, B. Black staining of tongue, C. Formication, D. Run amok', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Cocaine : Fatal dose: 1g oral/ 20 mg IV Chronic cocaine abuse: a) Ulceration of nasal septum / palate b) Peripheral gangrene c) Black color staining of tongue d) Cocaine bugs/ formication Chronic cannabis abuse: a. Amotivational syndrome b. Run amok: homicidal impulse/stabbing spree', 'role': 'assistant'}]