Following is a specific antidote for poisoning due to metoprolol:

Ans. C. GlucagonRef: Goodman & Gilman's The Pharmacological basis of Therapeutics 12th/ed, p317ExplanationB blocker overdosageTreatment* Common manifestations# Bradycardia (MC)# Hypotension# Prolonged AV conduction times, and widened QRS complexes* Other manifestations# Seizures and depression# Hypoglycemia and bronchospasm.* Significant bradycardia: initially atropine (option a) - cardiac pacemaker often required* Hypotension: Large doses of isoproterenol (option b) or an a agonist* Glucagon (option c): Acts through its own GPCR and independently of the b-adrenergic receptor, has positive chronotropic and inotropic effects on the heart and is used as antidote in p-blocker overdosage.If question was like this: Following are used for poisoning due to metoprolol except:a Atropineb Isoproterenolc Glucagond Verapamil Ans. d. Verapamil# Adverse effects depend on various properties of drug like receptor selectivity, membrane stabilizing property, etc. as follows:Adverse effects depend on the following properties of the drugCaution to be exercisedNon-selective b blocker* Worsening of asthma, COPD: b1 selective blockers preferred but should be used with caution* Worsening peripheral vascular disease: pi blockers well tolerated in mild to moderate PVD, used with caution in severe diseaseb blocker with intrinsic sympathomimetic activity* Preferred in patients prone to develop severe bradycardia with b blocker therapy* Are less useful in angina patients because of stimulation of heartb blocker with membrane- stabilizing properties* Avoid in glaucoma due to risk of Cornell anesthesiab blocker with low lipid solubility* Have less CNS adverse effects compared to more lipid soluble* C/l in renal failure, because are excreted primarily by kidney