World Health Organization (WHO) released the treatment manual of diarrhea in 2005. We aimed to investigate the rationale for selecting medications for acute infective diarrhea in Thai community pharmacies and to see if the selection complied with the WHO manual.A theoretical 18-year-old patient with acute infective diarrhea was used for interviews. The protocol and materials for the research were approved by Institutional Review Board. A total of 30 drugstore personnel were selected by convenience sampling and included. The first author manually coded, extracted for themes, and translated the transcript. Participants did not dispense oral rehydration salt because of the feeling that diarrhea was not severe.Absorbents were dispensed because they were perceived as the first-line medication for noninfective or mild diarrhea. Antibiotics were dispensed because of the concerns for the prognosis and the expected patient pressure. None provided zinc to the patient because of the lack of knowledge of the indication of zinc. We found that dispensing for acute infective diarrhea in Thai drugstores deviated from the WHO treatment guideline. The reasons were that the pharmacy personnel were not practicing evidence-based medicine, the lack of knowledge, the patient pressure, the unavailability of products, and the perceived availability of information in local guidelines.