Famphur.
21 C.F.R. § 558.254
in effectEffective: 2024-07-01(a) Specifications. Type A medicated articles containing 13.2 or 33.3 percent famphur.
(b) Sponsor. See No. 000061 in § 510.600(c) of this chapter.
(c) Related tolerances. See § 556.273 of this chapter.
(d) Special considerations. Famphur is a cholinesterase inhibitor. Do not use this product in animals simultaneously or within a few days before or after treatment with or exposure to cholinesterase-inhibiting drugs, pesticides, or chemicals.
(e) Conditions of use. It is used in cattle feed as follows:
Source: eCFRURL: https://www.ecfr.gov/api/versioner/v1/full/2024-07-01/title-21.xmlFetched: 7/26/2026
