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Title 21

Displaying title 21, up to date as of 10/15/2026. Title 21 was last amended 10/14/2026.
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§ 520.1199 Ivermectin, pyrantel, and praziquantel tablets.

(a) Specifications. Each chewable tablet or soft chewable tablet contains:

(1) 34 micrograms (mcg) ivermectin, 28.5 milligrams (mg) pyrantel pamoate, and 28.5 mg praziquantel;

(2) 68 mcg ivermectin, 57 mg pyrantel pamoate, and 57 mg praziquantel;

(3) 136 mcg ivermectin, 114 mg pyrantel pamoate, and 114 mg praziquantel; or

(4) 272 mcg ivermectin, 228 mg pyrantel pamoate, and 228 mg praziquantel.

(b) Sponsor. See No. 051311 in § 510.600(c) of this chapter.

(c) Conditions of use in dogs —

(1) Amount. Administer monthly according to body weight as follows:

(i) 6 to 12 lb: one tablet as described in paragraph (a)(1) of this section.

(ii) 12.1 to 25 lb: one tablet as described in paragraph (a)(2) of this section.

(iii) 25.1 to 50 lb: one tablet as described in paragraph (a)(3) of this section.

(iv) 50.1 to 100 lb: one tablet as described in paragraph (a)(4) of this section.

(v) Greater than 100 lb: use the appropriate combination of tablets.

(2) Indications for use. To prevent canine heartworm disease by eliminating the tissue stage of heartworm larvae (Dirofilaria immitis) for 1 month (30 days) after infection and for the treatment and control of roundworm (Toxocara canis, Toxascaris leonina), hookworm (Ancylostoma caninum, Uncinaria stenocephala, Ancylostoma braziliense) and tapeworm (Dipylidium caninum, Taenia pisiformis) infections.

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

[71 FR 65052, Nov. 7, 2006, as amended at 78 FR 28822, May 20, 2014; 83 FR 14587, Apr. 5, 2018]