Allergen: A substance that can trigger an allergic reaction. Asthma can be triggered by dust mites, animal dander, mold, and cockroaches.
PUVA: A form of phototherapy that combines the use of psoralens and ultraviolet light to treat skin disorders.
Hives: Elevated patches on skin usually caused by an allergic reaction accompanied by a release of histamine into the body tissues. Patches are redder or paler than the surrounding skin and itch intensely.