Many people have eyelid swelling at some point in their life. But this does not require any treatment since the swelling will settle down on its own. You can always apply warm compression for reducing the inflammation or take antihistamines. However you should never squeeze your eyes which may worsen the swelling.
Causes :
Several factors are responsible for causing swelling on the eyelids.
Allergy :
It can be caused due to allergic reactions by changing eyelid polishes or other cosmetics like hair spray or makeup. Allergy can also occur from pet animals. Sometimes eyelid swelling is caused due to abnormal reaction of immune system. If the eyes are left with allergen, automatic defense system of the eyes secretes histamines for protecting it which would make the eyelids to swell.
Blepharitis :
Blepharitis is a condition of eyelid inflammation which causes redness and irritation on the eyes. Your will have burning sensation or gritting feeling on the eyes when infected with blepharitis. Some people will feel as though sand is deposited inside the eyes during this situation which will cause swelling of eyelids.
Conjunctivitis :
This is caused due to bacteria or virus and sometimes due to potential allergens like dust, smoke. Even changing your contact lenses and eye drops can cause conjunctivitis leading to redness and swelling of eyelids. Stye is an eye infection caused by bacteria on the sebaceous glands forming cysts inside the eyes. This would also cause eyelid swelling and redness.
Chalazion :
When the oil glands of the eyes are blocked for some reason, it may cause swelling of eyelids with redness and itchiness. When the subcutaneous glands or tissues get inflamed (cellulitis) it may cause eye irritation and eyelid swelling. Some disease like diabetes or sinusitis can also cause swelling of eyelids and redness. Eyelid swelling and inflammation of retina can occur due to herpes infection.