Definitions.
21 C.F.R. § 335.3
in effectEffective: 2024-07-01As used in this part:
(a) Antidiarrheal. A drug that can be shown by objective measurement to treat or control (stop) the symptoms of diarrhea.
(b) Diarrhea. A condition characterized by increased frequency of loose, watery stools (three or more daily) during a limited period (24 to 48 hours), usually with no identifiable cause.
(c) Travelers' diarrhea. A subset of diarrhea occurring in travelers that is most commonly caused by an infectious agent.
Source: eCFRURL: https://www.ecfr.gov/api/versioner/v1/full/2024-07-01/title-21.xmlFetched: 7/26/2026