What potential side effect should a nurse inform a patient about when administering ophthalmic ointment?

When administering ophthalmic ointment, it is important to inform the patient that their vision may be blurred for a while after the application. This is because the viscosity of the ointment can temporarily impact visual acuity. The ointment is designed to coat the surface of the eye, which can lead to a temporary blurring effect until the ointment is absorbed or spreads adequately over the ocular surface. It is crucial for patients to understand this potential side effect so they can take appropriate precautions, such as avoiding activities like driving until their vision returns to normal.