<prompt> Which of the following drugs has no cycloplegic action?AtropineCyclopentolateTropicamidePhenylepherine  <response>: Ans. d Phenylephrine. Ref. KD Tripathi, Pharmacology, 4th ed., 88, Basak, Ophthalmology, 2nd ed., 44 Sympathomimetic mydriatics like atropine strongest cycloplegic, homatropine, cyclopentolate, tropicamide have cycloplegic action. Pure a-adrenergic agent - PHENYLEPHRINE Sympathomimetics is not cycloplegic. PILOCARPINE is a local parasympathomimetic ocular hypotensive drug whose mitotic effect is useful in the management of angle closure glaucoma. It is not a cycloplegic drug.Note: a -adrenergic agents such as phenylephrine or oxymetazoline are generally used topically to alleviate nasal congestion and obstruction. 