Bradycardia is common after injection of:

Ans. (B) Succinylcholine(Ref: KDT 8th/e p378)Succinylcholine is a depolarizing neuromuscular blocker. In contrast to ganglionic blocking properties of competitive neuromuscular blockers (like d-TC), it stimulates the ganglia.Initially bradycardia is seen due to stimulation of parasympathetic ganglion which is followed by tachycardia and hypertension due to stimulation of sympathetic ganglia.Dopamine and isoprenaline possess b1 agonistic activity and thus can cause tachycardia.Midazolam is a benzodiazepine. It does not affect CVS at therapeutic dose but produces bradycardia at toxic levels.