CFR > Title 21 - Food and Drugs > CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES > SUBCHAPTER E—ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS (parts 500 to 590) > PART 520—ORAL DOSAGE FORM NEW ANIMAL DRUGS > 520.1900—Primidone tablets.

520.1900—Primidone tablets.

(a) Specifications. Each tablet contains 50 or 250 milligrams of primidone.
(b) Sponsor. See No. 000010 in § 510.600(c) of this chapter for use of 250 milligram tablets; see No. 000856 in § 510.600(c) of this chapter for use of 50 and 250 milligram tablets.
(c) Conditions of use in dogs— (1) Amount. Twenty-five milligrams of primidone per pound of body weight (55 milligrams per kilogram of body weight) daily. 1

Code of Federal Regulations

Footnote(s): 1 These conditions are NAS/NRC reviewed and deemed effective. Applications for these uses need not include effectiveness data as specified by § 514.111 of this chapter, but may require bioequivalency and safety information.
(2) Indications for use. For the control of convulsions associated with idiopathic epilepsy, epileptiform convulsions, viral encephalitis, distemper, and hardpad disease that occurs as a clinically recognizable lesion in certain entities in dogs. 1
(3) Limitations. The tablets may be administered whole or crushed and mixed with the food. When convulsions are frequent, the dosage should be divided and administered at intervals. Reduction in dosage should be made gradually and never be abruptly discontinued. Do not use in feline species, as primidone appears to have a specific neurotoxicity in cats. Federal law restricts this drug to use by or on the order of a licensed veterinarian. 1

Code of Federal Regulations

[42 FR 61594, Dec. 6, 1977, as amended at 43 FR 55386, Nov 28, 1978; 46 FR 8467, Jan. 27, 1981; 46 FR 57477, Nov. 24, 1981; 53 FR 40727, Oct. 18, 1988; 56 FR 37473, Aug. 7, 1991; 62 FR 35076, June 30, 1997]