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What is Only mydriatic action is by- and explain in detail?
Ans. is 'c' i.e., Phenylepherine Phenylepherine is used as a mydriatic when cycloplegia is not required. It reduces the i.o.t. by constricting ciliary body blood vessels. It is also used as a nasal decongesent. About other options o Tropicamide, homatropine and cyclopentolate are mydriatic as well as cycloplegic.