Angiotensin converting enzyme inhibitors are a common cause of drug induced angioedema. Papular urticaria Idiopathic C. Clinical Features Index Urticaria consists of raised, erythematous skin lesions that are itchy, tend to be evanescent in any one location, and generally are worsened by scratching. Angio-oedema is a reaction similar to urticaria except that it occurs in deeper tissue and is characterised by asymmetrical swelling of tissue. Pruritus, however, is uncommon with angio-oedema which more typically has a burning sensation. Any area of the body may be involved, although the perioral and periorbital regions, tongue, genitalia and extremities are involved most frequently.
Laryngeal oedema is the most serious manifestation of angio-oedema.
D. Diagnosis Tests Index 1. A careful history and physical examination are the most important aspects of the evaluation of urticaria. The characteristics and distribution of the rash must be ascertained on examination. Laboratory Tests Laboratory tests are of limited value in the investigation of urticaria. Skin prick testing or RAST are generally not helpful.