Blepharitis: This is an inflammation of the eyelids that can cause swelling, redness, and itching. It's a common condition and often associated with other symptoms like crusting around the eyelashes and a feeling of grittiness in the eyes.

Allergic Conjunctivitis: An allergic reaction can cause swelling, redness, and itching of the eyelids. This condition is often seen in people with a history of allergies and can be triggered by allergens like pollen or dust.
Chalazion: A small bump on the eyelid due to a blocked oil gland. It can cause swelling and may become infected, leading to increased redness and pain.
Hordeolum (Stye): An infection of an oil gland or hair follicle on the eyelid, which can cause a painful, swollen lump.

Orbital Cellulitis: A serious infection of the tissues surrounding the eye, which can cause swelling of the eyelids, along with fever, pain, and decreased eye movement. It requires prompt medical attention to prevent serious complications.
Angioedema: A condition characterized by rapid swelling of the skin and mucous membranes, which can affect the eyelids. It can be a part of an allergic reaction and, in severe cases, can compromise breathing.
Thyroid Ophthalmopathy: Associated with Graves' disease, this condition can cause swelling of the eyelids, bulging of the eyes, and other eye symptoms due to autoimmune inflammation.

Sarcoidosis: A condition that can cause inflammation in various parts of the body, including the eyelids, leading to swelling and other symptoms.
Wegener's Granulomatosis (Granulomatosis with Polyangiitis): A rare autoimmune disorder that can affect many parts of the body, including the eyes, and cause swelling of the eyelids among other symptoms.
Xanthelasma: A condition characterized by small, yellowish patches or bumps on the eyelids due to accumulation of fat, which can sometimes be mistaken for swelling.