This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Forensic Medicine
Antidote in Atropine poisoning is ? 
Select and explain. 
A. Flumazenil, B. Physostigmine, C. Naloxone, D. NaHCO3
B: Physostigmine
Answer: B: Physostigmine 
Explanation: Ans. is 'b' i.e., Physostigmine Atropine blocks cholinergic receptors. So, for atropine overdose, we require a drug that increases cholinergic action. Physostigmine increases the concentration of Ach. Physostigmine counteracts central (because it crosses BBB) as well as peripheral symptoms of atropine toxicity (other anticholinesterases like neostigmine and pyridostigmine counteract only peripheral symptoms as they cannot cross BBB) Physostigmine is the DOC.