What condition would be indicated by swollen lips without an allergic cause?

Swollen lips without an allergic cause can be indicative of angioedema. This condition involves deep swelling beneath the skin and can occur in various locations, including the lips, eyelids, and throat. Angioedema can be triggered by various factors, including hereditary factors, medication reactions, or certain medical conditions, but it is not primarily an allergic response.

In contrast, contact dermatitis results from the skin's reaction to an irritant or allergen, which typically causes localized inflammation and may include redness, itching, and rash rather than swelling alone. Herpes simplex is a viral infection characterized by blistering lesions, often accompanied by other symptoms such as pain and tingling, rather than isolated lip swelling. Stomatitis refers to inflammation of the mucous membrane of the mouth, which may cause symptoms in the oral cavity but does not specifically indicate isolated swelling of the lips.

These distinctions clarify why angioedema is the most appropriate condition associated with swollen lips without an allergic cause.