A swollen eyelid occurs when there is inflammation or excess fluid (edema) in the connective tissues surrounding the eye. Swollen eyes can be painful and non-painful, and affect both the upper and lower eyelids. There are numerous causes of a swollen eye, including eye infections, eye injuries or trauma, and, most commonly, allergies. Generally, if your swollen eyes are due to allergies, antihistamine eye drops or oral allergy medication, as well as lubricating artificial tears will help relieve symptoms. Your eye doctor also may recommend mild steroid drops for more severe allergic reactions. Other causes, such as infection like conjunctivitis or ocular herpes, respond well to anti-viral or anti-inflammatory eye drops or ointments, or antibiotics. Minor bouts of swollen eyelids can be eased with home remedies. First and foremost, avoid rubbing your eyes as this will only aggravate your condition.