Section 520.2612 - Trimethoprim and sulfadiazine suspension(a)Specifications. Each milliliter (mL) of suspension contains: (1) 10 milligrams (mg) trimethoprim and 50 mg sulfadiazine; or(2) 400 mg combined active ingredients (67 mg trimethoprim and 333 mg sulfadiazine).(b)Sponsors. See sponsor numbers in § 510.600 of this chapter: (1) No. 000061 for use of product described in paragraph (a)(1) for use as in paragraph (c)(1) of this section.(2) No. 051072 for use of product described in paragraph (a)(2) for use as in paragraph (c)(2) of this section.(c)Conditions of use -(1)Dogs -(i)Amount. Administer 1 mL (10 mg trimethoprim and 50 mg sulfadiazine) per 5 pounds (lb) of body weight once daily, or one-half the recommended daily dose every 12 hours, for up to 14 consecutive days.(ii)Indications for use. The drug is used in dogs where systemic antibacterial action against sensitive organisms is required, either alone or as an adjunct to surgery or debridement with associated infection. The drug is indicated where control of bacterial infection is required during the treatment of acute urinary tract infections, acute bacterial complications of distemper, acute respiratory tract infections, acute alimentary tract infections, wound infections, and abscesses.(iii)Limitations. Federal law restricts this drug to use by or on the order of a licensed veterinarian.(2)Horses -(i)Amount. Administer orally at a dosage of 24 mg combined active ingredients per kilogram body weight (10.9 mg/lb) twice daily for 10 days. Administered by volume at 2.7 mL per 45.4 kilograms of body weight (2.7 mL/100 lb).(ii)Indications for use. For the treatment of lower respiratory tract infections in horses caused by susceptible strains of Streptococcus equi subsp. zooepidemicus.(iii)Limitations. Do not use in horses intended for human consumption. Federal law restricts this drug to use by or on the order of a licensed veterinarian. 78 FR 63872 , Oct. 25, 2013, as amended at 85 FR 4208 , Jan. 24, 2020 As amended at 85 FR 4208, 1/24/2020