A 59-year-old female was started on oral carbamazepine for her psychological disorder on April 21 2004. Four weeks later, she developed generalized erythemas on the trunk and extremities, and ran a high fever of 38°C. A physical examination showed erythroderma, and laboratory examination revealed liver dysfunction and hypereosinophilia. Three days after admission, a number of small pustules emerged on the erythrodermic backgrounds. The skin lesions were improved by the withdrawal of carbamazepine and systemic prednisolone (50mg per day). However, acute pancreatitis was also developed during the course. HHV-6 IgG was increased up to x1280 on June 17. Also, HHV-6 DNA was detected with two peaks during the therapy. DLST with carbamazepine showed a high titer of stimulation index. This case was unique in the acute generalized exanthematous pustulosis (AGEP)-like clinical appearance and the development of acute pancreatitis. HHV-6 DNA was increased with double peaks, which might suggest a “re-reactivation” of HHV-6 by carbamazepine.