Certified Ophthalmic Assistant Practice Exam

What powerful mydriatic and cycloplegic agent requires up to two weeks for its effects to diminish?

1. Cyclopentolate

2. Atropine

3. Phenylephrine

4. Scopolamine

The correct answer is: Atropine

Atropine is recognized as a powerful mydriatic and cycloplegic agent that can take up to two weeks for its effects to diminish. It works by blocking the action of acetylcholine on the ciliary body and the sphincter muscle of the iris, leading to dilation of the pupil (mydriasis) and paralysis of the ciliary muscle (cycloplegia). This prolonged duration of action makes atropine valuable in certain clinical situations, including the management of uveitis and for performing comprehensive dilated eye exams. In contrast, while other options like cyclopentolate and scopolamine are also mydriatics, they typically have shorter durations of action—often only a few hours to a couple of days. Phenylephrine, on the other hand, is primarily used for pupil dilation but does not produce cycloplegia and also has a shorter duration of effect. These differences in duration and action help clarify why atropine stands out in this context.