Hello. i woke up with a swollen eye yesterday. i wear prescription spectacles. today the eye is still swollen and itchy sometimes. what could be the cause? do i need to visit a gp or optician for consultation?

This may resolve: Without pain or significantly blurred vision this is unlikely to be a serious issue. Most of the time swelling around the eyelids with itching is due to contact with an irritating agent- something on your pillow or rubbed into your eye- or could be a new chalazion (stye = blocked oil gland in eyelid). Try warm wet compresses and wash the area gently with a mild face soap like CeraVe.