This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
A patient presented in emergency with tachycardia,hypehermia,bronchial dilation and constipation.The person is likely to be suffering from overdose of 
Select and explain. 
A. Atropine, B. organophosphorus compound, C. Mushroom, D. Paracetamol
A: Atropine
Answer: A: Atropine 
Explanation: Ref:KD Tripathi pharmacology 7th edition (page.no: 114,115) Actions of Muscarinic antagonist (atropine) CNS stimulation CVS: the prominent effect is tachycardia by abbretes refractory period of AV node and facilitate AV conduction Gland; decrease salivary, tracheobronchial and lacrimatory secretion, gastric secretions Smooth muscle: decrease tone and contraction, bronchodilatation, constipation Eye; mydriasis by contraction of longitudinal ciliary muscle Rise in body temperature (hypehermia)