There are many reasons for you to wear an eye patch, and different eye patches for each reason.
If your eye has been injured or has undergone surgery:
Your eye may be vulnerable to infection or greater injury, until it heals.
After surgery, your doctor may want you to wear an eye patch, to prevent your eye from getting infected or wet, which increases the chance of infection.
After surgery, if your eye needed stitches (sutures) to close an incision, a patch may be needed to prevent infection. A patch also prevents the possibility that the sutures might come apart, from something touching or rubbing the eye.
Do not drive or operate machinery while wearing a patch. Remember that having one eye covered eliminates your depth perception and your ability to judge distances.
TYPES OF PATCHES
Hard shell patches:
Many eye specialists like to be extra careful, and will have you use a hard shell covering over a patch. Or they will have you use the hard shell by itself, over your eye, if they feel it is safe for your eye to be open. This type of patch adds extra protection from any blow to the eye area.
A pressure patch is used in specific situations. For example, it is used when the doctor wants the surface of the clear covering at the front of the eye (cornea), to heal rapidly. The patch stops any interference from the normal blinking of the eye. The pressure patch prevents blinking, allowing the cornea surface to heal.
A pressure patch is usually thick, and taped in a special way to your cheek and forehead, so that constant pressure is applied to your eye. It must be put on properly, to avoid too much pressure. Too much pressure can damage the eye. Too little pressure allows the eyelid to move under the patch.
People may use patches for cosmetic reasons, to hide an unsightly or absent eye.
SEEK IMMEDIATE MEDICAL CARE IF:
You have increased eye pain.
You develop a discharge from your eye, that is clear and watery or thick in consistency.
Your pressure patch loosens up, and needs to be replaced.