Atropine is substituted by phenylephrine to facilitate fundus examination when?
Ans. is 'a' i.e., Mydriasis required without cycloplagia o Anticholinergic drugs (atropine) cause i) Mydriasis ii) Paralysis of ciliary muscles (cycloplegia) o Adrenergic drugs (phenylephrine) cause i) Mydriasis ii) Has no action on ciliary smooth muscles --> no cycloplegia For fundoscopy only mydriasis is required (no cycloplegia is required) --> Phenylephrine is preferred over atropine.
Mydriasis required without cycloplagia
Cycloplegia is required
Mydriasis and cycloplegia both required
Cycloplegia and mydriasis both are not required