How Much Penicillin Can I Give My 45-Pound Dog Safely?

Determining the appropriate dosage of penicillin for dogs is a crucial aspect of veterinary care. The recommended dosage varies depending on the species of the animal. For dogs, the typical dosage falls within the range of 10 to 40 milligrams per kilogram (mg/kg) of the dog’s body weight. This dosage can be administered intravenously (IV), intramuscularly (IM), or subcutaneously (SC), and the frequency of administration is generally every 6 to 12 hours.

In the case of horses, the recommended dosage is typically 15 to 40 mg/kg, administered either intramuscularly or intravenously, and given every 6 hours.

Cattle, on the other hand, require a dosage of 4.4 to 11 mg/kg when administered intramuscularly, and this should be given every 24 hours. Alternatively, a higher dose of 22 mg/kg can be administered subcutaneously every 12 hours.

For small ruminants and camelids, the recommended dosage is usually between 10 to 20 mg/kg, and it can be administered through IV, IM, or SC routes, with a frequency of every 8 to 12 hours.

It’s important to note that the specific dosage may vary based on the individual animal’s condition and the veterinarian’s assessment. Always consult with a qualified veterinarian to determine the precise dosage and administration schedule for your pet.

For a 30 lb dog, the recommended dose of injectable penicillin is 90 mg (30 lbs x 3 mg/lb) administered twice daily via subcutaneous or intramuscular injection. It’s important to note that this dosage is specific to dogs and cats. For cattle and calves, including non-ruminating (veal calves), the recommended dosage ranges from 60 mg to 150 mg (2 mg to 5 mg/lb) of body weight once daily, administered via intramuscular injection. It’s crucial to consult a veterinarian for precise dosing instructions based on the specific animal and its condition.

Dosages of Penicillins

Species	Dosage
Dogs	10–40 mg/kg, IV, IM, or SC, q 6–12 h
Horses	15–40 mg/kg, IM or IV, q 6 h
Cattle	4.4–11 mg/kg, IM, q 24 h; or 22 mg/kg, SC, q 12 h
Small ruminants and camelids	10–20 mg/kg, IV, IM, or SC, q 8–12 h