This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: NEET Jan 2020, Subject name: Forensic Medicine
Magnan's symptom is seen in: 
Select and explain. 
A. Datura, B. Cocaine, C. Opium, D. Cannabis
B: Cocaine
Answer: B: Cocaine 
Explanation: Altered tactile sensation: the person feel that some insects are crawling on his skin. This is known asMagnan's symptomorcocaine bugs(formication). Cocaine is an alkaloid derived from plantErythroxylon coca.