Children generally use pupil dilating medication during their eye exams, and there is some dilatation and photophobia during the pupil dilatation period, and how long it takes to recover is generally related to the type of pupil dilating medication used. The most common types of medications are as follows: 1. Atropine Eye Gel: It is a long-acting pupil-diluting agent, and it takes about three weeks for the pupil to return to its original size. 2. Safeguard: Also known as cyclopentolate hydrochloride eye drops, its effectiveness can be maintained for three days, which means that the pupil returns to normal after three days. 3. The most commonly used is called tropicamide, which is only effective for about six hours, for example, the day the pupil returns to normal. However, it is important to listen to your doctor’s advice on which dilating medication to use, because the power of adjustment varies by age, and choosing the right medication can have an impact on the results of optometry or other tests if it is not appropriate.