<prompt> Pupil fails to dilate by giving cocaine inCentral sympathetic paralysisCentral parasympathetic paralysisPeripheral parasympathetic paralysisPeripheral sympathetic paralysis.  <response>: In periphery cocaine blocks the uptake of Adrenaline and Noradrenaline in Adrenergic nerve ending resulting in higher concentration of sympathetic neurotransmitters Sympathomimetic effect :The peripheral sympathomimetic action of cocaine produces following effect :MydriasisRise in B.P.Local vasoconstrictionTachycardiaTherefore if the peripheral sympathetic system is paralysed it will lead to reverse of the above mentioned actions. 