Objective: This study aimed to report the improvement of a patient with chronic insomnia who was treated with Baekho-tang based on the Shanghanlun disease pattern identification diagnostic system (DPIDS).

Methods: The patient’s symptoms were checked on days 19, 37, and 52 after taking Baekho-tang. Chronic insomnia was evaluated by the degree of insomnia, hours spent asleep, and the number of times the patient woke up during the night, which were all assessed by a visual analog scale (VAS) with the Leeds Sleep Evaluation Questionnaire. In addition, new clinical implications for the interpretation of the 350th Shanghanlun provision were reviewed.

Results: After administering Baekho-tang for 52 days, based on the 350th Shanghanlun provision according to the DPIDS, the VAS score decreased from 10 to 1.

Conclusions: The patient recovered from chronic insomnia. This case report suggests that the words “滑,” “厥,” and “裏” in the 350th provision of Shanghanlun mean physical and psychological causes of insomnia. In addition, Baekho-tang had a therapeutic effect in improving the chief complaint of the patient. Therefore, the interpretation of the 350th Shanghanlun provision requires a new definition that includes the patient's lifestyle, family conflict, and past history of the patient as a cause of chronic insomnia.

Key words: Insomnia, Baekho-tang (白虎湯), Shanghanlun, disease pattern identification diagnostic system