A client who is taking sildenafil 50 mg by mouth (PO) as needed (PRN), reports experiencing visual changes to the practical nurse (PN). Which instruction should the PN give to the client?

Report the symptoms to the healthcare provider immediately.

Instill prescribed eye drops now and then three times a day.

Encourage wearing dark glasses when outside to protect the eyes.

Monitor for visual changes each morning using an Amsler grid tool.