Which is the shoest acting mydriatic?: (A) Tropicamide, (B) Atropine, (C) Phenylephrine, (D) Hyoscine
Answer is A. Tropicamide is the quickest (20-40min) and shoest acting (3-6hours) mydriatic. Atropine is a potent mydriatic but its slow and has long lasting action. With it, pupil dilates in 30-40min but cycloplegia takes 1-3hours.