Sagging eyelids is the condition in which the skin on and around your eyelids droops or hangs down instead of staying taut. Drooping eyelids can occur in one or both eyes and around either the upper or lower lids. Sagging eyelids are most often just an annoyance, but in some severe cases, the sagging of skin can interfere with your vision. The causes of sagging eyelids range from normal aging to medical conditions that affect the nerves and muscles in your face.

Age

Eyelid drooping, called ptosis, happens to many people as they get older according to the National Institutes of Health. As you age, the protein called collagen, which supports your skin, begins to break down, making your skin thinner and more likely to sag. Some people are born with droopy eyelids, while others might experience sagging as they reach middle adulthood.

Injury

Permanent or temporary injuries to the face and eye could lead to sagging eyelids according to the NIH. Styes, small localized infections of the oil glands near the eye, could cause sagging eyelids until the area has healed. Facial nerve injuries or migraine headaches could also cause your eyelids to droop.

Muscle and Nerve Disorders

Medical conditions that affect the nerves or muscles in your face can cause your eyelids to sag. Myasthenia gravis is a condition in which your muscles have weakened and may affect many of your motor activities, such as eating, talking and walking. When myasthenia gravis affects your upper facial area, your eye muscles may not be able to hold up your eyelids properly and you may experience sagging. Horner syndrome is another disorder that can cause sagging eyelids, because the nerves in your face do not send messages to your muscles the way they should.