A swollen eyelid is usually associated with allergy, injury, inflammation, infection, fluid retention, or sometimes cancer. Eyelid swelling accompanied by unusual symptoms can also be a sign of a severe condition requiring urgent medical attention. Seek emergency medical care if you experience swollen eyelids along with head trauma, sudden vision impairment, neck stiffness, high fever, severe headache, or general swelling throughout the body. You should also go the emergency room if you have protruding or bulging eye(s) with redness, fever and pain, or anaphylaxis symptoms. Anaphylaxis signs include itching, swollen tongue, lips or mouth, and wheezing or feeling like your throat is tight.