The patient was a 13-­year-­old male who had experienced periodic fever since he was in the 5th grade. After he moved into the 8th grade, he developed fever, abdominal pain, and vomiting continuously, which caused him to miss school or leave school early once every one to two weeks. Various Kampo extract preparations prescribed at a nearby clinic did not improve the symptoms, and the patient was referred to our hospital. Ad­ministration of bukuryoshigyakuto and shokenchuto reduced the fatigue, but the fever could not be controlled. Subsequently, a grasp of “the disease byakugobyo turned into fever” was made, and he was put on byaku­gokassekisanryo, which eliminated the fever. Therapeutic approaches for disease known as the disease ebyo that arises after treatment of cold damage diseases (shokan) are discussed in the On Pulse Syndrome Complex and Treatment of Bai He, Hu Huo, and Yin Yang Du Diseases section of the synopsis of prescriptions of the golden chamber “Kinkiyoryaku”. Children, especially adolescents, are prone to fall ill because of rapid changes of the body, including sexual maturation. Clinical manifestations of such illnesses further change with growth and maturation, and it can be difficult to find clues for treatment at first glance due to complicated states of yin­yang and deficiency-­excess. As seen in this case, illnesses of adolescence is likely to include un­diagnosed cases of byakugobyo that manifests clinical signs similar to those of ebyo.