Because direct and indirect ophthalmoscopy are best done through a dilated pupil, about 15 to 30 minutes before this examination, mydriatics (such as one drop of cyclopentolate 1% and one drop of phenylephrine 2.5%, for adults) can be instilled when there is no contraindication to a dilated eye examination (eg, shallow anterior chamber, allergy, ruptured globe) and with caution in pregnancy.