StacksVerified U.S. regulatory reference

21 CFR §558.254

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)Specifications. Type A medicated articles containing 13.2 or 33.3 percent famphur.
  2. (b)Sponsor. See No. 000061 in § 510.600(c) of this chapter.
  3. (c)Related tolerances. See § 556.273 of this chapter.
  4. (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.
  5. (e)Conditions of use. It is used in cattle feed as follows: