It could be due to an allergic reaction to something or even because of an insect bite. An oral anti-biotic course may be required. Anti-allergics may also be required. If the swelling is very intense, it is also possible to be due to orbital cellulitis which is an ocular emergency as I/V anti-biotics may be required. Any infection in the adjoining areas like mouth, sinus or ears predisposes to that. It is always better to see an ophthalmologist in person so that an examination can be done. Thanks.
If there is a stye, you will have a painful bump near the lid margin. It could be red and may be filled with pus. Lid swelling may be present but is usually localized. Warm compresses are helpful. An oral anti-biotic course is needed. An anti-biotic eye drop like Vigamox should also be used to prevent eye infection. An anti-biotic eye ointment may also be applied at bedtime. Stye is also a possibility but an examination is recommended. Thanks.
Warm cmpresses along with an antibiotic eye ointment. Thanks.