Cholinergic urticaria with associated angio-oedema.

Three patients are described who developed angio-oedema and urticaria after a hot bath challenge and physical exercise. In one patient this was accompanied by a fall in peak expiratory flow rate. Blood levels of smooth muscle biological activity, measured using a bio-assay, increased in all patients after experimental challenge. The association of angio-oedema with cholinergic urticaria is emphasized and possible mechanisms discussed.