Swelling, usually acute, non-pitting.  May be erythema too.  Typically affects face, especially lips, tongue, eyes, but can be limbs, even internal!

Usually related to urticaria (wheals). As with urticaria, can be allergy – clue is consistent trigger, pattern of recurrent episodes – but can have other causes.

Angioedema without urticaria – consider hereditary or drugs, especially NSAIDs and ACE inhibitors.