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Title 21

Displaying title 21, up to date as of 6/04/2026. Title 21 was last amended 6/03/2026.
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§ 520.763b Dithiazanine powder.

(a) Specifications. Each tablespoon of powder contains 200 milligrams (mg) dithiazanine iodide.

(b) Sponsor. See No. 069043 in § 510.600(c) of this chapter.

(c) Conditions of use in dogs

(1) Indications for use and amount. Administer orally by mixing in food as follows:

(i) For large roundworms (Toxocara canis, Toxascaris leonina): 10 mg per pound (/lb) of body weight for 3 to 5 days;

(ii) For hookworms (Ancylostoma caninum, Uncinaria stenocephala) and whipworms (Trichuris vulpis): 10 mg/lb of body weight for 7 days;

(iii) For Strongyloides (Strongyloides canis, Strongyloides stercoralis): 10 mg/lb of body weight for 10 to 12 days;

(iv) For heartworm microfilariae (Dirofilaria immitus): 3 to 5 mg/lb of body weight for 7 to 10 days. Treatment for heartworm microfilariae should follow 6 weeks after therapy for adult worms.

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

[79 FR 28820, May 20, 2014, as amended at 83 FR 48945, Sept. 28, 2018]