Section 520.1326a - Mebendazole and trichlorfon powder(a)Specifications. Each gram of powder contains 83.3 milligrams of mebendazole and 375.0 milligrams of trichlorofon.(b)Sponsor. See No. 000061 in § 510.600(c) of this chapter.(c)Conditions of use in horses - (1)Amount. 8.8 milligrams of mebendazole and 40 milligrams of trichlorofon per kilogram of body weight.(2)Indications for use. It is used in horses for the treatment of infections of bots (Gastrophilus intestinalis and G. nasalis), large roundworms (Parascaris equorum), large strongyles (Strongylus edentatus, S. equinus, S. vulgaris), small strongyles, and pinworms (Oxyuris equi.)(3)Limitations. Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian.45 FR 10759, Feb. 19, 1980, as amended at 46 FR 52330, Oct. 27, 1981. Redesignated at 51 FR 13212, Apr. 18, 1986, as amended at 62 FR 61625, Nov. 19, 1997; 78 FR 28824 , May 20, 2014