More than 15 million Americans have allergic rhinitis alone, and approximately 12 million have other allergic manifestations such as urticaria, angioedema, eczema, or sensitivity to food, drugs, or insect bites. Almost 10% of patients who seek care at a physician's office do so for one of the common allergic diseases, but rating impairment for allergic disorders is uncommon because typically they do not produce “permanent” impairment and are not work- or liability-related. Section 9.3a, Respiration in Chapter 9, Ear, Nose, Throat, and Related Structures, of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) addresses the process of assessing impairment due to allergic rhinitis, the first type of allergy. Because allergic rhinitis is seasonal, the examiner must determine if permanent impairment is present and if the patient is at maximum medical improvement. The second major manifestation of allergy is allergic skin disease, including urticaria-angioedema and is discussed in Chapter 13, The Skin, where a table classifies skin disorder impairments. The third primary manifestation of allergic disease is eczema, also called atopic dermatitis, which also is discussed in Chapter 13. Allergic diseases are common but generally are quite treatable. Evaluators should ensure that the patient has had an appropriate trial of therapeutic agents before assigning a permanent partial impairment; because of treatment options, the latter should be rare.