1 When there is inflammation in the eye, the ciliary body may spasm, causing pain. Administering a cycloplegic eye drop will temporarily paralyze the ciliary body and calm the eye down to a level where the patient is much more comfortable.

Which I drop inactivates the sphincter muscle of the iris?

Mydriatic drops work by either inhibiting the parasympathetic pathway to the iris sphincter or by promoting the sympathetic pathway to the iris dilator.

What is mydriasis and cycloplegia?

A mydriatic is an agent that induces dilation of the pupil or mydriasis, whereas cycloplegia refers to paralysis of the ciliary muscle, thereby inhibiting accommodation or focusing ability.