Dosages of Penicillins

Sodium penicillin G

Cattle

20,000 U/kg, IV or IM, q 6 h

ELDU

Horses

10,000–20,000 U/kg, IV or IM, q 6 h

20,000–25,000 U/kg, IV, q 6–8 h

Doses up to 44,000 U/kg have been used in refractory cases

Potassium penicillin G

Turkeys

1.5 million U/gal, PO in drinking water, q 24 h for 5 d

Meat withdrawal time, 1 d

Horses

20,000–25,000 U/kg, IV, q 6 h

Doses up to 44,000 U/kg have been used in refractory cases; injectable potassium penicillin G contain considerable potassium content (1.7 mEq/million U) and should be used with caution in horses with HYPP and other sensitive patients

Procaine penicillin G

Cattle

22,000–66,000 U/kg, IM or SC, q 24 h

Doses >6,600 U/kg/d constitute ELDU

Horses

22,000–44,000 U/kg, IM, q 12–24 h

Swine

15,000–40,000 U/kg, IM, q 24 h

Doses >6,600 U/kg/d constitute ELDU

Camelids

22,000–44,000 U/kg, SC, q 12–24 h

ELDU

Benzathine penicillin G

Beef cattle and calves

12,000–40,000 U/kg, IM, q 48 h

Greatly extended withdrawal times for production animals should be anticipated; doses >8,800 U/kg constitute ELDU

Penicillin V

Dogs and cats

15,000 U/kg or 8–10 mg/kg, PO, q 6–8 h

Dicloxacillin sodium monohydrate

Dogs

11–55 mg/kg, PO, q 8 h

Cloxacillin sodium

Lactating dairy cattle

200 mg/quarter, intramammary, q 12 h for 3 doses

Meat withdrawal time, 10 d; milk withdrawal time, 48 h

Cloxacillin benzathine

Dry dairy cattle

500 mg/quarter, intramammary, once at dry-off

Meat withdrawal time, 28 d

Ampicillin sodium

Cats

6.6–20 mg/kg, IV, IM, or SC, q 8–12 h

Dogs

10–40 mg/kg, IV, IM, or SC, q 6–12 h

Horses

15–40 mg/kg, IM or IV, q 6 h

20–40 mg/kg IV, q 6 h for foals

Cattle

4.4–11 mg/kg, IM, q 24 h; or 22 mg/kg, SC, q 12 h

ELDU

Small ruminants and camelids

10–20 mg/kg, IV, IM, or SC, q 8–12 h

ELDU

Swine

22 mg/kg, SC, q 12 h

ELDU

Ampicillin trihydrate

Dogs, cats

6.6 mg/kg, IM or SC, q 12 h

Injection is a suspension; should not be administered IV due to risk of anaphylaxis and death

Cattle

4.4–11 mg/kg, IM, q 24 h

Swine

6.6 mg/kg, IM, q 12–24 h

Ampicillin-sulbactam

Dogs, cats

10–30 mg/kg, IV, q 6–8 h; 3.75–8.3 mg/kg/h, IV as a constant-rate infusion

Amoxicillin

Dogs, cats

11–30 mg/kg, PO, SC, or IV, q 8–24 h

Poultry

100–125 mg/kg, PO, q 8–12 h

ELDU; antimicrobials administered via medicated feed to food-producing species require a VFD in the US

Amoxicillin-clavulanate

Cats

62.5 mg per cat, PO, q 12 h; 10–20 mg/kg, PO, q 8 h

Dogs

12.5–25 mg/kg, PO, q 8–12 h

Poultry

125 mg/kg, PO, q 8–12 h

ELDU

Ertapenem

Dogs

30 mg/kg, SC, q 12 h

Reserved class, not for empiric treatment

Cats

30 mg/kg, IV or SC, q 8 h as needed

Reserved class, not for empiric treatment

Imipenem cilastatin sodium

Dogs, cats

5 mg/kg, IV, q 6–8 h

Reserved class, not for empiric treatment. May lower seizure threshold.

Horses

10–25 mg/kg, IV, q 6 h

Reserved class, not for empiric treatment

Foals

5 mg/kg, IV infused over 20 minutes, q 6–8 h

Reserved class, not for empiric treatment

Meropenem

Dogs, cats

8 mg/kg, SC, q 12 h; 12–24 mg/kg, IV, q 8 h

Reserved class, not for empiric treatment

Ticarcillin-clavulanate

Dogs, cats

25–50 mg/kg, IV or SC, q 8 h

Reserved class, not for empiric treatment