Inclusion Criteria:  Meets the diagnostic criteria for probable AD according to the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS/ADRDA) Scored 1.0 by the Clinical Dementia Rating Scale (CDR) Global Score  Exclusion Criteria:  Dementia due to other causes Evidence of a clinically relevant or unstable psychiatric disorder Has irritable bowel syndrome or inflammatory bowel disease Has unstable or severe cardiovascular, hepatic, renal, respiratory, endocrinologic, neurologic diseases and other conditions that, in the investigator's opinion, could interfere with the analyses of safety and efficacy in this study Has visual or hearing disorder, defeating completion of evaluation Use of AD therapy (except for donepezil hydrochloride) which cannot be stopped Use of antibiotics within 1 month prior to enrollment Has a history of gastrointestinal surgery (except for appendicitis and hernia surgery) Without a reliable caregiver who will accompany the participant during treatment and assessment, and monitor administration of the prescribed medications With cardiac pacemaker or metal allergy Once experienced electroacupuncture treatment before at any time (manual acupuncture is allowed) Premenopausal woman