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Title 21

Displaying title 21, up to date as of 6/16/2026. Title 21 was last amended 6/15/2026.
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§ 524.838 Esafoxolaner, eprinomectin, and praziquantel.

(a) Specifications. Each milliliter (mL) of topical solution contains 12 milligrams (mg) esafoxolaner, 4 mg eprinomectin, and 83 mg praziquantel.

(b) Sponsor. See No. 000010 in § 510.600(c) of this chapter.

(c) Conditions of use

(1) Amount. Administer the entire contents of a provided unit applicator topically once a month at a minimum dose of 0.055 mL/lb (0.12 mL/kg), which delivers a minimum dose of 0.66 mg/lb (1.45 mg/kg) esafoxolaner, 0.23 mg/lb (0.51 mg/kg) eprinomectin, and 4.55 mg/lb (10.0 mg/kg) praziquantel.

(2) Indications for use. For the prevention of heartworm disease caused by Dirofilaria immitis. Kills adult fleas (Ctenocephalides felis) and is indicated for the treatment and prevention of flea infestations, the treatment and control of Ixodes scapularis (black-legged tick) and Amblyomma americanum (lone star tick) infestations, and the treatment and control of roundworms (fourth-stage larval and adult Toxocara cati), hookworms (fourth-stage larval and adult Ancylostoma tubaeforme; adult Ancylostoma braziliense), and tapeworms (Dipylidium caninum) in cats and kittens 8 weeks of age and older, and weighing 1.8 lbs or greater.

(3) Limitations. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

[88 FR 55566, Aug. 16, 2023]