Swollen, watery eyes are a distinctive form of eye irritation, mainly caused by infectious diseases of the eye. This type of disease can cause congestion and oedema of the eyelid skin and conjunctiva, resulting in swollen eyelids, involuntary tearing, and in some cases, incomplete eyelid closure.
The most common cause is acute conjunctivitis, which is characterised by swollen eyelids, redness, tearing and a foreign body sensation, and may be accompanied by increased discharge.