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Title 21

Displaying title 21, up to date as of 6/11/2026. Title 21 was last amended 6/11/2026.
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§ 520.1242b Levamisol boluses or oblets.

(a) Specifications. Each bolus contains 2.19 grams levamisol hydrochloride. Each oblet contains 0.184 grams levamisol hydrochloride.

(b) Sponsors. See Nos. 000061 and 054771 in § 510.600(c) of this chapter.

(c) Required labeling. Consult your veterinarian for assistance in the diagnosis, treatment, and control of parasitism.

(d) Related tolerances. See § 556.350 of this chapter.

(e) Conditions of use

(1) Cattle

(i) Amount. Administer orally 2.19-gram boluses as a single dose as follows: 250 to 450 pounds, 12 bolus; 450 to 750 pounds, 1 bolus; and 750 to 1,050 pounds, 112 boluses.

(ii) Indications for use. Anthelmintic effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum), and lungworms (Dictyocaulus).

(iii) Limitations. Conditions of constant helminth exposure may require re-treatment within 2 to 4 weeks after the first treatment. Do not slaughter for food within 48 hours of treatment. Not for use in dairy animals of breeding age. Consult veterinarian before using in severely debilitated animals.

(2) Sheep

(i) Amount. Administer orally one 0.184-gram oblet for each 50 pounds of body weight.

(ii) Indications for use. Anthelmintic effective against the following nematode infections: Stomach worms (Haemonchus, Trichostrongylus, Ostertagia), intestinal worms (Trichostrongylus, Cooperia, Nematodirus, Bunostomum, Oesophagostomum, Chabertia), and lungworms (Dictyocaulus).

(iii) Limitations. Conditions of constant helminth exposure may require re-treatment within 2 to 4 weeks after the first treatment. Do not slaughter for food within 72 hours of treatment. Consult a veterinarian before using in severely debilitated animals.

[78 FR 28822, May 20, 2014]